Sudden Hate!!

Totsuzen dai-kirai!! (突然大嫌い!!) is the 230th chapter of the manga it is also the first chapter of the Reversal Jewel Arc.

Cologne lets Shampoo choose a piece of antique jewelry from her collection. Shampoo chooses a brooch from a box, not knowing about its effect turning her love for Ranma into hate.

Mysterious Brooch
It's a normal day in Nerima as Shampoo goes through her usual routine of crashing her bike into Ranma to greet him. The onlookers are unfazed and Akane walks past trying to ignore it. Shampoo returns to the Cat Café where Cologne is rummaging through her old jewelries. She lets Shampoo pick one out for herself and takes her leave. She takes a liking to a brooch that was inside a small chest.

Next day, Ranma and Akane are rushing to school when Ranma is again hit by Shampoo. But this time, instead of being greeted with hugs, he is met with an uppercut to send him flying.

While in class, Akane asks Ranma what happened between them, but Ranma is unable to figure it out. Ranma decides to go to Shampoo to see if something really did happen. He takes Hiroshi and Daisuke and visit the Cat Café. They find Shampoo inside, but she is actively avoiding Ranma. When he tries getting close to her, she starts slapping him for touching her.

The cold stare she gives afterwards is enough to get Mousse's attention, who was well aware of the look. He claims that she now hates Ranma 120 times more than him. This statement suddenly attracts all his classmates to the Cat Café to hear about her change of heart. Ranma is both confused and embarrassed that he is put under such a spotlight.

Brooch's Secret
Akane asks Cologne what may have happened, upon which Cologne recognizes the brooch on Shampoo. The brooch is able to control the wearer's emotion. When in the upright position, it amplifies the person's love, while in the upside down position, it turns the love it has for a person into hate. She realizes what Shampoo had done (unintentionally), but does not tell Akane about this.

Back home, Akane patches Ranma up from Shampoo's slapping frenzy. She asks him what he might have done to her, but he is not able to figure it out. Their conversation attracts Nabiki and Soun who thought they heard that Shampoo and Ranma were through. Ranma is unable to accept that he has been dumped by Shampoo and calls her out to meet him.

Shampoo is not pleased to see Ranma again but shows up. When they meet on a rooftop, he asks Shampoo to give a reason why she hates him. Shampoo beckons him closer to whisper into his ear, and when he leans in, screams into his ear then gives him another beating before launching him off of the roof. Watching from afar, Cologne realizes the potential in having the brooch on Shampoo. She figures that if Shampoo actively shows disinterest towards Ranma, he will actively seek after her. Ranma gets up from the roof he landed on and loudly proclaims that he will make Shampoo love him again no matter what. The cry is loud enough to be heard by Akane, who breaks the dish she was washing in surprise.

Cast in Order of Appearance

 * Shampoo (human)
 * Akane Tendo
 * Ranma Saotome (male)
 * Hiroshi and Daisuke
 * Sayuri
 * Cologne
 * Mousse (human)
 * Soun Tendo
 * Nabiki Tendo
 * Kasumi Tendo

Trivia

 * The Reversal Jewel is also referred to as the Contrary Jewel, according to the first OVA.