Kairaishi Mushroom

The Kairaishi Mushroom is a magical mushroom that comes from an unclear location.

Appearances
Kairaishi Mushrooms appear in the manga's Kairaishi Mushroom Arc and the anime's 3rd season episode Sneeze Me, Squeeze Me, Please Me! Shampoo's Recipe For Disaster, which is an adaptation of the former.

In the manga, the mushrooms were delivered to the Nekohanten by accident as part of a delivery of supplies, with Cologne noting that she had not ordered the mushrooms. Shampoo did not recognize the fungus, requiring her grandmother to explain (and demonstrate) how it worked to her.

In the anime, it is implied that Shampoo ordered the mushrooms deliberately for herself after coming up with a scheme to use them on Ranma Saotome.o

Powers
When ingested, Kairaishi Mushrooms render the consumer open to irresistible hypnotic suggestions. The "imprint" window is relatively short - a few minutes at most. During this time, a person can give a verbal instruction and a signal to the consumer. Once the "imprint" window closes, they will be compelled to enact the instruction whenever they hear the trigger sound. This compulsion lasts for an uncertain amount of time, but clearly spanning multiple hours. Until it wears off, the consumer cannot resist their urge to obey this imprinted instruction.

Users
Shampoo uses Kairaishi Mushroom-laden products to try and get Ranma Saotome to hug her when she snaps her fingers. Instead, a nearby cat sneezes, unintentionally setting it that Ranma will instead hug whoever sneezes. Over the course of the evening, he involuntarily hugs many different people, upsetting Akane Tendo.

Ranma then gets back at Shampoo, who has invaded the Tendo Dojo to try and take advantage of the situation, by forcefeeding her a Kairaishi Mushroom shumai herself, compelling her to return home when he snaps his fingers.