Diamond Head

Ichihashi Nanao is an incredibly bright girl and the first to ever transfer into Mehabia Catholic School. The one God here, though, is the "Judicature Club," a school-sanctioned means of resolving student disputes. Its president and judge is the first person Nanao meets--Hanegi Raika, a handsome boy who looks like a girl. This highly selective club wants Nanao as a member, but while she may be unwilling to judge others, she may have no choice when she herself is judged.

Source: ShoujoMagic