Tsubasa Kurenai is a suitor of Ukyo Kuonji who followed her to Furinkan after she left her old school. Despite appearing to be a girl, Tsubasa, like most of Ukyo's suitors, is actually a male to female cross-dresser.

Prior to the events of the series, Tsubasa attended an all-boys school which was also attended by Ukyo at the time (who'd disguised herself as a boy). Tsubasa quickly fell in love with Ukyo and began showering her with gifts, but Ukyo had no attraction to Tsubasa. Even after Ukyo left to find Ranma, Tsubasa still sent mountains of love letters to Ukyo, prompting her to send Tsubasa a letter explaining about her engagement along with a picture of Ranma's female form.

Tsubasa ended up having Ukyo agree to let him help her with her restaurant to deliver okonomiyaki -- decided mostly because she wouldn't have to pay him much. During his deliveries, Maomolin (who also works part-time at a restaurant, but at Shampoo's Cat Café stall) instantly fell in love with him and routinely chases him around asking him to be his bride, much to Tsubasa's dismay. Strangely enough, even after Tsubasa reveals to Maomolin that he's actually male, Maomolin declares that it doesn't bother him as nobody's perfect. And the chase continues on...

Tsubasa also makes use of various disguises (mostly during battles, but oftentimes for no particular reason than to make an ostentatious appearance out of nowhere). He has made full use of disguising as a tree, a letterbox, a trash can, a vending machine, a washing machine, and Ucchan's Okonomiyaki sign, among others.

(Source: Ranma Wikia)