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?
Unfortunately, that's not possible. 
The dead can't come back to life.
Es ist sehr traurig,
Lo siento por él,
Lo siento por él,
C’est malheureux,
Per quanto mi spiaccia,
É uma pena, mas não há possibilidade de
trazer de volta aqueles que morreram...
Прости, Коёми, но что бы мы ни делали,
мёртвых вернуть нельзя.