日向 陽一

A high school student and sole survivor of a tragic spaceplane crash that robbed him of both his family and memories roughly two years prior. Amnesiac but steady in his new life, Youichi manages to find solace in surrounding himself with friends.

Everything changes, however, when an unidentified object crash-lands in Youichi's hometown and he meets Aries, a mysterious – and similarly amnesiac – young girl from outer space.