Amakawa Haruto, a twenty year old university student, loses his life when the bus he is on gets into an accident. As his consciousness begins to fade, his one regret is not telling his childhood friend, Miharu, how he felt. She'd disappeared after their high school entrance ceremony.
Now we move to the slums of the Kingdom of Beltrum. In a corner of a filthy shack, a boy named Rio moans and wakes from a nightmare. He has lived only to take revenge upon a certain man, but now, in his mind, suddenly there are flashes of another version of himself living in a world he's never seen before—the memories of Amakawa Haruto.
Not at all! We're the ones who 
should be apologizing to you.
.لا شكر على واجب! نحن من يجدر بهم الاعتذار منك
Nicht doch. Wenn, dann muss
ich mich eher entschuldigen.
¡No me des las gracias!
¡Nosotros deberíamos pedirte perdón!
Non,
c’est plutôt à moi de m’excuser.
Ma no, che dici? Siamo noi che
dovremmo scusarci con te, piuttosto.
De nada, somos nós quem
devemos nos desculpar com você.
Что ты! Это мы должны 
извиняться перед тобой.