Toki no Kawa wo Koete

Toki no Kawa wo Koete (時の河を越えて lit. Crossing the River of Time) is a song covered by Mikami Kamiki, Yuki Tojo, and Tsubomi Hiiragi.

It was originally sung by Ushirogami Hikaretai and used as the sixth opening theme of [https://en.wikipedia.org/wiki/High_School!_Kimengumi High School! Kimengumi].