While struggling to make friends after his parents’ divorce, Koyomi Takasaki meets Kazune Takigawa, but apparently, they already have. Kazune reveals that she’s from World Line 85, an alternate universe in which she and Koyomi are lovers. But in a reality where moving between dimensions is natural, could Koyomi be the one from another world?
It was when I was in high school 
that I met Koyomi Hidaka.
Ich habe Hidaka Koyomi
in der Oberschule kennengelernt.
Conocí a Koyomi Hidaka en preparatoria.
Conocí a Koyomi Hidaka en bachillerato.
J’ai rencontré Koyomi Hidaka
au lycée.
Io ho incontrato Koyomi Hidaka
 quando facevo il liceo.
Eu conheci o Hidaka
Koyomi no ensino médio.
Сама я познакомилась с ним
только в старшей школе.