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?
She said her life was happy, 
and I was very happy about that.
Und diese Person hat gesagt,
sie ist glücklich.
Me dijo que era feliz
Me ha dicho que era feliz
Pourtant, elle m’a dit
qu’elle était heureuse…
Ma mi ha detto che è felice.
Mas ela disse que agora é feliz.
Но она сказала,
что сейчас очень счастлива.