Okuremashite Seishun summary:

Wakaba (20) is a college debutante who yearns for youth. When she goes out on Halloween dressed in her school uniform, she ends up going on a date with a high school boy named Tachibana!　But in fact, this boy is also a college student whose friend left him out of the date... In order to make Wakaba's dream come true, she is asked to continue going out with him on his Seifuku dates!