What if you meet my friend's childhood after ten years of separation? It was just as Mitsuya, who was recently translated by the head of the company, who found that a person living in the three doors of his new apartment was not someone else, as not, the best friend of his older brother ... and his first love. When she was a young, rapid high school student, Mitsuya kissed Nobor firmly and scared him. Deeply regretting your act, he held back his feelings. But now again to be with the door-it is to return all these hot memories, as if they never went from the very beginning. "Merry Checker" is adapted from this manga.