Ashita mo Mata Yuusha no Tonari

Mao Kurose can't stop thinking about Kanade Momomiya, the classmate sitting next to her. Unable to sort out her feelings, Kurose discovered memories of her past life as the Demon Lord, and recalled the moment that the Demon Lord killed the Hero. The Hero with the exact same face as Momomiya.
Here comes a girls-love story that transcends time!
(Souce: Comic NewType, translated)
Note: Chapter count includes an interlude chapter.