The main character of the manga Prunus Girl, alongside Maki. He declares himself a boy at the beginning of the first chapter, despite his girly-looking appearance and personality. He's athletic but not a very good student, and has a sweet tooth.

Aikawa wears the girls' school uniform at Midorinoka (he tried wearing the boys' uniform at one point, to the awe of his classmates, but found it didn't suit him as well), and cross-dresses outside of school, too. He's very girly and comfortable with this, but is quick to remind everyone of his true gender, and occasionally worries his cross-dressing is holding back his masculinity (he wonders if that's why he's stopped growing taller, for instance).

People are often shocked or creeped out to learn Aikawa is male, but his classmates largely treat him like a girl. He's popular with boys and girls, and many of the boys leer at him and chase after him in the same way they treat their female classmates. He often flirts with Maki, and the other characters often remark that the two of them seem like a couple. Aikawa usually shies away from serious romantic intimations towards Maki, though, saying nothing can happen between them since they're both guys.