Shampoo met Ranma when Ranma (as a girl) and Genma (as a panda) drop into a contest in a village of the Joketsuzoku ("Chinese Amazons") and the pair gorged themselves on the feast for the winner of the village's martial arts contest. As village champion, Shampoo challenges them. Ranma defeats her, but according to Chinese Amazon tribal laws, if a female Amazon is defeated by a female outsider, she must give the outsider the "Kiss of Death," hunt her down to the ends of the Earth, and kill her. Ranma and Genma escape, and settle down in Nerima, Japan.

Tracking Ranma to Japan, Shampoo encounters the male Ranma, who stops her from attacking Akane by knocking the ball off her bonbori and knocking her out. And if a female Amazon is defeated by a male outsider, she has to marry him. So she continues on the path of trying to marry male Ranma and kill female Ranma, until Ranma tricks her into thinking that the male side is a disguise for the female side.

She returns to China to undergo specialized training from her great grandmother Cologne. It is at this time she falls into the Cursed Springs and receives her cat curse.

Learning that Ranma is cursed as well, she goes back to Japan to marry him. She works with her great grandmother at the Neko Hanten as a waitress/cook/delivery girl.

At first glance, Shampoo might seem like a bimbo, due to her simplified mode of speech, but she's also had a limited amount of time to learn the Japanese language, after pursuing Ranma to his home country. This tendency may be exaggerated in western translations, although her grammar isn't shown to improve after her second appearance, while she was presented as speaking fluent Chinese during a rooftop talk with Mousse. In the Memorial Book, Shampoo is described as 'innocent and aggressive,' which is an accurate summation of the dichotomy of her simultaneously cheerful, open, affectionate, hard-working, spiteful, sadistic, murderous and manipulative personality. Despite her frequently harsh treatment of other people and occasionally even towards Ranma himself, her love for him seems genuine.

Having been trained in the martial art techniques of the Joketsuzoku since birth, with Cologne as her personal instructor and the young female village champion, Shampoo is highly skilled in unarmed combat, particularly involving speed and acrobatics, and is strong enough to casually walk through walls on a regular basis. Despite this, she uses a pair of bonbori as her primary weapons, but is also shown using sword, spear, bow, and a variety of polearms; however, she apparently doesn't remotely compare to Ranma himself, and was completely outmatched and effortlessly overpowered the few times she's seriously faced him in one-on-one combat.

Beyond basic fighting ability, Shampoo has displayed knowledge of ventriloquism/voice imitation, shiatsu-induced unconsciousness, mind-control or memory loss, sleep-fighting, intuitive multi-step strategy, defense against enchanted herbs, Chinese cooking, and incredible tracking-skills enabling her to hunt Ranma from rural China to the east of Japan. She also has access to minor magic equipment, and is capable of using her bike to literally bounce across the city. Her true strength may lie in sheer versatility.

(Source: Wikipedia)