Shampoo is introduced during the 15th episode of the Ranma 1/2 TV series. First impressions aren't always the best as she's seen trying to kill female Ranma. Later on she falls in love with male Ranma and is torn between killing his female side or loveing his male side. She leaves but later returns and plays a major part in the Ranma 1/2 series as another fiancee of Ranma's. Having the strongest feelings for Ranma, she stops at nothing to try get him to marry her.
Shampoo (yeah no last name) is from an Amazon tribe in China. Amazon tribal law states that when defeated by a female outsider, you must give them the "kiss of death". That basically means that you'll hunt them to the ends of the earth until you kill them. If however you are defeated by a male outsider, you must marry them. Luckily for Ranma he defeated her while in his female form and also accidentally while in his male form. Hence he was both hated and loved by Shampoo. After finding out that Ranma is half male and female, she leaves heartbroken but returns later with her great grandmother Cologne.
Having already been engaged to Akane and not wanting to marry Shampoo, Ranma ends up having to deal with constant tricks and blackmailing by Cologne and Shampoo. Although sometimes amusing in the results, Shampoo stops at almost nothing to get rid of anything between herself and Ranma. Sometimes it involves killing Akane, erasing her memory, blackmailing Ranma to marry her, and countless other things.
After returning to China shamed by not having killed female Ranma or marrying male Ranma, her great grandmother Cologne decided to work on her training so they went to the springs of Jusenkyo. Unfortunately for her, Shampoo got knocked into the springs of drowned cat. From then on whenever she gets splashed by cold water she turns into a small white kitten. Although she doesn't really mind the curse, she sometimes uses it to get back at Ranma since he is terrified of cats.
With her and her grandmother's buisness of making ramen, she ends up following and setting up shops wherever Ranma goes. As a result of her strong feelings for Ranma, she appears almost everywhere and plays a major role in the anime as an obstacle between Ranma and Akane. For some people, Shampoo is one of their favorite characters. This is probably since she has such a bubbly personality, is so devoted, and can actually cook ;)
Jusenkyo Curse:
Whenever she gets splashed with cold water she turns into a small white kitten. She loses all her clothes but still retains those hair bead thingies.
Family:
She has her great grandmother Cologne and I think that's it.
Weapons/Skills:
Her main set of weapons are ..I believe they're called bomborii's but they're basically metal balls with a stick attached like a mace. She's used a sword before but that about limits the weapons unless you consider her bike. She's trained in martial arts and a few other techniques (like erasing Akane's memory for example) and also probably has the most strength out of all of Ranma's suitors.
Possible Suitors:
Ranma Saotome
Mousse
Rivals:
Akane Tendo
Ukyo Kuonji