Oira Sukeban (1992)

Does being the only guy in an all girl school sound like paradise? It might be, if the girls knew you were a guy, but to stay in school teenage pervert Banji can't let can't let anyone find out his chromosomes don't match. Banji's status conscious parents want him to go to a good school, but not enough to spend the money on a good co-ed school. Now, in addition to studying math and science, Banji has to learn how to put on a bra and makeup. His life has become a living hell. Not only is he at the bottom of the social pecking order, he must also got to conceal his inner-masculinity from the pretty classmate girl who's stolen his heart while avoiding the female bullies who threaten to expose his less-than-feminine charms in the locker room. (Source: ANN)