Hikaru is a common Japanese name that means "flashing brilliance". Gosunkugi is a pun whose kanji can mean "five inch nail". 
Gosunkugi has short, dark hair and characteristic dark circles under his eyes. This is most likely genetic as both of his parents have this characteristic. He is skinny and typically wears the gakuran worn by male students at Furinkan High School. When performing his voodoo rituals he straps candles to his head. In the Nightmare! Incense of Spring Sleep OVA Gosunkugi's skintone is a ghostly white.
Gosunkugi is a quiet, antisocial individual, noted by his classmates as tending to blend into the background. He is shy and uncertain, but has something of a vengeful streak and is rather obsessive, particularly when it comes to things that interest him greatly, like the occult or Akane. He is also somewhat of a daydreamer.
Little is known about Gosunkugi's past, except that he has always been an outcast and has, like the majority of Ranma's rivals, been in love with and pursuing Akane Tendo. His family share his large absent minded eyes and presumably his social distance with others. Many of the girls at school make an effort to be polite to him in person, though Yuka and Sayuri said he was strange when he was out of hearing range. Ranma took quite some time to finally notice him; his friends pointed out Gosunkugi is not the type you would notice as he hangs out at the back of the class by himself.
Tatewaki Kuno pays Gosunkugi for the photos he takes in hopes of discovering Ranma's weak spot. Eventually after spending a significant amount of time stalking Ranma he discovers it to be a fear of cats. He sent Ranma a letter (badly disguised to be a letter of help from Akane that "she" had been kidnapped and was held hostage in the gym). Dressed as Akane, Gosunkugi pleaded for Ranma to save him, while secretly luring him into two traps designed to send him into the basement under the gym, full of cats. Both traps failed as Ranma easily evaded them, while they both backfired on Gosunkugi, Akane however fell into the gym. In a bid to save her Ranma goes down to but finds Gosunkugi having placed fish sausages on him. Ranma immediately sees the room is full of cats and using every bit of his will power manages to refrain from screaming at the sight of the cats, while taunting Gosunkugi, whilst Gosunkugi becomes confused Ranma becomes near paralysed. Akane tries to drag Ranma out and accidentally went into a room where Gosunkugi had placed a tiger (in another attempt to scare Ranma). The tiger forced all three of them to the corner of the room so Ranma was confined with a large number of cats. This was too much for him to bear and his neko-ken activated. While this happened Kuno had assembled a party above for winning over the 'pig-tailed girl' when once he had exploited Ranma's weakness. He and a large number of students witnessed a large number of cats being blown out of the basement along with a tiger. Neko-Ranma emerges and in a fury shreds Kuno's sword with sir swipes, but eagerly runs after the shredded sword when Kuno throws it out of the gym. Later when Akane and Ranma's friends desperately try to send Ranma out of the neko-trance Ranma bounds to Akane and purrs upon her lap, and unintentionally kisses her. Gosunkugi manages to photograph this incident. Whilst nailing the photo onto a power line pole rather like a voodoo doll, Ryoga shows up and in a fit of anger punches and breals the power line. Later he and Gosunkugi confront Ranma with the photo (which Ranma had no recollection of), but are pushed away by Ranma. The events of this arc, Akane's rage at Ranma kissing her as well as Shampoo coincidentally showing up from China in an express delivery in her cat form. She witnesses that Ranma is actually a boy under a Jusenkyo curse, sets off the next arc. The cat's tongue pressure point arc.
Romeo Juliet Play
Gosunkugi is one of the many characters to 'audition' for the play upon discovering that Akane was playing Juliet. He along with Ranma, Kuno and Happosai all fought over the part for Romeo. Though Ranma was the only one who went for the part with no desire to have alove scene with Akane but was after the reward to 'see China'. Gosunkugi however was the only one who had no ability in combat, so he suggests instead of the guys usual method of fighting to settle their problems, to use a contest of drama and acting to settle the dispute on stage. As the other three fought on stage, Gosunkugi disguised himself as part of Juliet's balcony so he could do the love scene with Akane whilst the others fought. He was however spotted by the others and is quickly put out of action. Later however Ranma turns into a girl in order to put his rivals out of action by seducing them, as a second Juliet. Ranma manages to put both Happosai and Kuno out of action by intoxicating Happosai with sake, distracting him with a bra and then trapping him in a barrel that she nails shut. While taking care of Kuno by letting his guard down by "kissing him" with tape over his mouth, and then tying him up. However in the confusion Gosunkugi manages to use chloroform to knock out Akane, but fails to drag her away as she is too heavy for him. After this Ranma and Kuno boot Gosunkugi away and he does not show up for the rest of the play. Later Ranma receives the unpleasant surprise that "seeing China" was not in fact a chance to go to China for free but the holding of a China themed party, Gosunkugi is seen among the people enjoying the party.
Akane vs Kodachi - Cookie Battle (The Way the Cookie Crumbles)
Gosunkugi photographs an incident with Ranma lying on Kodachi.
Ultimate Moxibustion Arc (The World's Weakest Man)
When Happosai used the devastating weak point moxibustion on Ranma, he spread leaflets saying "Ranma is weak" causing all of Ranma's adversaries to come rushing over to beat him up. Gosunkugi is among them, but waits until Ranma has received a very thorough beating by his other rivals, Principal Kuno, Mousse and Kuno, before striking Ranma with his hammer. He charges at Ranma along with his other rivals but is booted away along with the others by Ryoga, who had stepped in to save his weakened rival. Gosunkugi is not seen for the rest of the arc.
Gosunkugi waits until 6:30 AM when Akane passes by on her morning jog. He tries to catch up to her and talk, but she runs too quickly for him to keep up. A salesman notices his plight and sells him some magical paper dolls. Later that day, Gosunkugi is having a P.E. lesson with Ranma and other male students from his class. Gosunkugi decides to see if the dolls really work by writing "fall down" on one, before placing it on Ranma's back just before he has to use a Horizontal bar. At first Ranma seems not to be affected by the doll, until he tries to dismount, where he slips and lands on top of Gosunkugi. Ranma apologises to Gosunkugi, to which Gosunkugi tells Ranma it's alright. As Ranma talks to Hiroshi and Daisuke, who, like Ranma, can't believe he actually fell down, Gosunkugi is overjoyed that the dolls actually work. With evidence the dolls work, Gosunkugi tries use one on Akane saying "Go on a date with me!". However, just before he can put it on Akane's back, she notices him and asks if there's anything she can do for him. Akane speaking to him after such a long time causes Gosunkugi to become overjoyed and become so self indulged by it that he forgets about the doll as Akane looks on in confusion. Back in class and Hiroshi and Daisuke tell Ranma that Gosunkugi put something on his back just before he used the Horizontal bar. Ranma is a bit skeptical, but Hiroshi demonstrates what Gosunkugi did with the doll that Gosunkugi meant to use on Akane earlier. The doll soon takes affect and Ranma goes on a date with Gosunkugi (much to Gosunkugi's distaste). Eventually Gosunkugi is forced to put another doll on Ranma commanding him to stop. Gosunkugi decides to deal with Ranma first so prepares a doll which commands him to argue with Akane. He tries to put it on Ranma's back, but Ranma soon notices Gosunkugi, grabs him by the scruff and asks what he's doing this time. Akane then appears and tells Ranma not to bully the weak. While Gosunkugi is overjoyed yet again that Akane defended him, Ranma and Akane begin arguing. Gosunkugi tries to interject, saying he hasn't put the doll on Ranma yet, but is quickly pushes aside by the pair telling him they can deal with there own problems alone. This causes Gosunkugi to try yet another doll, this time telling Ranma to injure himself. When Gosunkugi tries to put it on Ranma, he easily avoids all of Gosunkugi's attempts. Ranma eventually causes Gosunkugi to fall to the floor, where Ranma tells him that he'll never get that thing on his back in a million years. Gosunkugi just thinks to himself, telling Ranma to just wait. Some time passes and Gosunkugi places a doll on the teacher which commands him to seat him behind Ranma. The teacher moves the whole class around, and sure enough Gosunkugi ends up behind Ranma. Initially Gosunkugi thinks to himself about how Ranma has no escape now, but just then Akane sits next to Ranma (as per where the teacher moved her). Gosunkugi begins cursing Ranma for turning his plan against him so he could sit next to Akane. Gosunkugi then suddenly realises he only has one paper doll left and screams at the thought, causing everyone to turn and look what's going on. Akane notes that Gosunkugi is acting very strange, to which Ranma adds that he's been telling her all along that Gosunkugi's crazy. This causes Gosunkugi to panic and write "Please don't hate me!" on his last doll, which he finally manages to place on Akane's back. Akane quickly turns to Gosunkugi and tells him not to be silly as she has no reason to hate him. As Akane returns to doing work, Gosunkugi is delighted at this comment. A few minutes later, Gosunkugi realises his mistake as he should've written "Love me" on his last doll instead...
Gosunkugi appears briefly behind Ranma during a scene.
Reversal Jewel (Say You Love Me!!)
Gosunkugi appears briefly in the desk behind Ranma when he is studying a magazine on how to be popular with girls.
One Punch Armour (One-Punch)
Gosunkugi is surrounded by a group of three street thugs, all of whom are wearing masks. The thugs say that if Gosunkugi hands all his money over they won't hurt him... much. Gosunkugi decides that he better introduce himself, as he does so he goes and gets a nail and hammer out of his satchel. At first he seems willing to hand them over, but Gosunkugi actually attempts to hit one of the thugs with them. However, the thug manages to avoid the nail and the group decide to start beating up Gosunkugi. Shortly after the thugs begin beating up Gosunkugi, Ranma arrives and defeats the thugs with ease. Ranma then notices that it was Gosunkugi who was getting beaten up. After Ranma asks if he's alright to which Gosunkugi replies he's fine and thanks Ranma for his help. Akane then appears and asks Ranma is he's trying to pick another fight. Ranma replies that he was just helping Gosunkugi since he was in trouble. Akane then asks Gosunkugi if he's not hurt. Seeing Akane's concern delights Gosunkugi and he says that he's sorry for her to see him like this. Ranma then tells Gosunkugi that it's fine since Martial Artists have to protect the weak and downtrodden. Ranma and Akane then leave. As Gosunkugi watches them leave he becomes very angry at Ranma's belittling of him in front of Akane. Gosunkugi then begins talking to himself how much he despises Ranma, but Gosunkugi continues saying that Ranma isn't all bad since he saved him. He then begins to walk off, continuing to say that he can't talk to Akane since he knows Ranma will belittle him. He then wishes there was a way for him to become just as strong as Ranma, if not even stronger than him! Gosunkugi is in his room, reading a magazine. He then comes an advertisement for the One-Punch Armor, where a man named Jack Seiler talks about how buying the armor has allowed him to get all the women he ever wanted, as well as making him able to defeat all his enemies. Needless to say Gosunkugi orders one of the suits. When the suit arrives Gosunkugi tries it on and then begins to fantasise about him defeating Ranma and Akane finally falling for him. However, Gosunkugi is unable to stand up while wearing the suit because of how heavy it is. Ranma receives a letter from Gosunkugi (who hasn't be seen at School for the past three days), challenging him to a duel; the letter also tells Ranma to pick up Gosunkugi from his house. Ranma does as the letter asks and goes to Gosunkugi's house. When he arrives, Ranma sees Gosunkugi with his parents having some tea. Gosunkugi explains to Ranma that he couldn't move because of the suit so he had to bring Ranma to him. When Ranma asks why Gosunkugi didn't just take the suit off he explains that he couldn't since it has an automatic lock for safety reasons. Gosunkugi continues to explain to Ranma that if he doesn't punch his strongest opponent once the lock stays on and he can't remove the suit. Ranma then hits Gosunkugi in the back of the head and says that's a though break, Ranma then continues to ask Gosunkugi is this means he's his strongest rival. Gosunkugi replies yes and tells Ranma he's as quick as ever. Gosunkugi then releases a chain from the arm of the suit and is able to stand up finally, much to delight of his parents. Once he stands up, Gosunkugi punches table in front of him, this leads Gosunkugi to deduce that the suit waits for the enemy to come into range; it then latches onto them and powers up. As he says this Gosunkugi's parents are glad their son finally grew a backbone and is now practicing martial arts. The suit then prepares to punch Ranma again, as Gosunkugi asks Ranma to let him punch him just once so he can get rid of the suit. Ranma says there's noway he'd allow that and tells Gosunkugi to give it his best shot. Gosunkugi then swings at Ranma, but it just manages to dodge it, causing the wall behind him to be hit instead and crumble. Gosunkugi then comments of the power of the suit and how incredible it is, he then realises with this he can finally defeat Ranma and runs off to Furinkan High School (dragging the still chained Ranma with him). Gosunkugi and Ranma prepare to begin their fight, while a large number of students gather around them. Ranma then asks Gosunkugi if it isn't enough for him to defeat him, but he has to do it front of the student body as well. Gosunkugi explains to Ranma that just facing him in a fight is thrilling and that beating Ranma to a bloody mess is just a bonus. Akane then runs towards the fight, shouting to Ranma that him facing Gosunkugi is like kicking a puppy, but she quickly stops when she sees Gosunkugi spinning Ranma in the air by the chain to the suits arm. Gosunkugi then throws Ranma to the ground. Hiroshi and Daisuke (who had come to watch the fight) say that this is surreal, while Akane wonders what in the world is going on. Having seen Akane, Gosunkugi tries even harder to defeat Ranma, but after throwing a punch which misses Ranma sees his chance and manages to kick Gosunkugi. Continuing the onslaught, Ranma hits Gosunkugi with several punches to the chest. However, Gosunkugi simply stands up afterwards saying to Ranma that his punches won't do anything to him so long as he wears the suit. Ranma begins to worry as to how he's going to win. Just then the suit begins to beep and a countdown begins on the front of the suit. At first Ranma and Gosunkugi wonder what the countdown is for, but then the suit says that the battery will fail in five minutes. Hearing this Ranma decides to have another stab at fighting Gosunkugi. Daisuke asks if this means that if Gosunkugi can't punch Ranma in five minutes Ranma wins. Gosunkugi replies, while trying to punch Ranma, that it isn't quite like that and the suit will explode if he doesn't manage to hit Ranma. A number of students then run away in horror. Gosunkugi goes in for a punch but misses again. Hiroshi and Daisuke try and convince Ranma to let Gosunkugi punch him, but Ranma refuses. Akane then joins in and angrily tells Ranma to just let Gosunkugi punch him. Ranma replies, equally as angrily, that this is a fight between honourable men and that Gosunkugi won't be satisfied with a hollow victory. Gosunkugi is touched that Ranma has respect for him, but the countdown is down to 10 seconds and he doesn't want to explode. Gosunkugi then tries for one last punch at Ranma, but Ranma stops the punch from connecting so the suit explodes. Gosunkugi then falls over as Ranma declares his victory. Meanwhile, Akane calls Ranma an idiot and Gosunkugi lies on the ground saying once he feels his body again he'll congratulate him. Daisuke just calls Gosunkugi and Ranma a pair of idiots.
Hinako Ninomiya Intro (The Ultimate Teacher!)
Gosunkugi appears on the title page of "The Ultimate Teacher!".
Gonsunkugi briefly appears behind Ranma in a scene.
Pill Box (A Package from Mother)
In one scene, Akane ends up digging out a wara ningyo. Meanwhile, Gosunkugi is next to Ranma curiously looking at the box that he found while burying the cursed doll. In anger Ranma kicks Gosunkugi into the air, before being kicked by Akane for copying her act.
Gosunkugi briefly appears behind Ranma in one scene.
The Final Chapter
Gosunkugi appears with everyone else who got invited to Ranma's and Akane's wedding, though he is sobbing.
Gosunkugi's parts in the Neko-Ken and Romeo and Juliet Arcs were given to Sasuke Sarugakure. He was eventually introduced in the anime-original episode "Enter Gosunkugi, The New Rival!?" as a transfer student. Gosunkugi would later appear in "The Case of the Furinkan Stalker!", "Akane Goes to the Hospital!", "Gosunkugi's Paper Dolls of Love", "Gosunkugi's Summer Affair!", and the OVAs "Shampoo's Sudden Switch - The Curse of the Contrary Jewel" and "Stormy Weather Comes to School! Growing Up With Miss Hinako". Gosunkugi also has a brief cameo in Big Trouble in Nekonron, China. In the 2008 OVA adaptation of Nightmare! Incense of Spring Sleep, Gosunkugi's role is expanded.
Gosukugi's fighting ability is extremely limited and he is also quite weak, which forces him to rely on guile and underhanded means. He has a tendency to let the main fighters do combat while he takes the prize they are fighting over when they are too busy to notice. When he is forced to fight he wields a small hammer, with or without the use of nails. His name, meaning "Five Inch Nail", makes reference to his usage of nails. Despite his fixation on the occult and constant attempts to perform rituals, he has no magical abilities. He is consistently targeted by the school bullies and is usually saved by Ranma from them.
Gosunkugi made two attempts to seriously challenge Ranma in a fight. When Happosai hit Ranma with the Ultimate Weakness Moxibustion, reducing his strength to that of a baby's, Gosunkugi seized his chance. He was able to land a strike with his hammer, but was unable to follow up thanks to Ryoga's intervention. In the One-Punch Armor Arc, Gosunkugi brought a special armour which gave him temporary power, but it was too heavy for him to move on his own and only worked if he was handcuffed to Ranma. He was then given a chance to punch Ranma in 30 minutes or the armour would explode. Gosunkugi failed to accomplish this as Ranma dodged his predictable attacks and the armour blew up.
Like many of the other male characters in the series, Gosunkugi is in love with Akane Tendo, even though he is too shy to tell her. He usually stands longing along the sidelines watching the more potent characters such as Ranma or Kuno battle over her, and on occasion hatching a non-violent plan to overthrow his rivals in love to win Akane for himself. Most notable in the Neko-ken Arc he goes to a lot of trouble in teaming up with Kuno in order to exploit Ranma's weakness, which he eventually discovered was cats, and then setting several traps to expose Ranma's ailurophobia to the whole school, hence shaming Ranma and winning Akane. His plan failed as at first Ranma kept dodging the traps, whilst they back fired on him, and also when Ranma was placed in a room full of cats (and a tiger) he not only succeeded in hiding his ailurophobia, but his neko-ken activated and was turned into a potent force of destruction.
Though not friends and normally rivals, Gosunkugi has toadied up to Kuno to get revenge on Ranma in several storylines.
In the anime his reason for hating Ranma and loving Akane is more personal. When Gosunkugi first arrives in Nerima, Ranma accidentally knocks him down while he is first coming to Furinkan High School, whereas Akane helps him up and speaks nicely to him. Things are cemented when Akane tries to offer a boxed lunch she made to Gosunkugi, Ranma having refused it, and Ranma immediately tries to snatch it back. Though Ranma is merely trying to prevent Gosunkugi from having an agonizing stomach ache, this makes him look like he bullies Akane to Gosunkugi, and then, for added measure, Ranma accidentally spills Akane's lunch all over Gosunkugi's head.
Gosunkugi is a playable character in the video game Ranma ½: Hard Battle. In the live action special he is portrayed by Yuta Kanai. He wears the alternate uniform worn by male students at Furinkan and uses a Canon EOS DSLR.
- The small straw dolls that Gosunkugi is always seen carrying around are called wara ningyo and can also be made from paper. Wara ningyos are a common feature in many Shinto rituals, with uses from casting love spells to warding off sickness to driving away yokai and evil spirits. Particularly in the latter categories, nailing them to objects or pounding nails into them is a common theme.
- The ritual that Gosunkugi is frequently seen performing is a form of cursing ritual from the 800s. Dressed in white and either wearing candles on their head (a common feature for Shinto rituals involving the spirit world) or carrying a torch in their mouth, the caster comes to a tree or a shrine gate at the hour of the ox (between 1 and 3 AM) and nails one or more wara ningyos to it while calling upon the kami to curse the individual they hate. This needs to be done on at least three days to at most seven days to work, and for best results the dolls should be nailed in place facing the northeast. According to the yin-yang philosophy, this is the direction from which all evil spirits come.
- Although introduced in the sixth season, Gosunkugi can be seen briefly in the intro to the fifth season Earth Orchestra.
- His voice actor, Issei Futamata, provided the voice of characters from 2 other anime adaptations of Rumiko Takahashi's manga series: Chibi from Urusei Yatsura and Yusaku Godai from Maison Ikkoku.