10th -You and I fell in love with the same person.-
Nii-chan (harada)
So this is a really twisted plot. On a first note, the negligence of both families makes their kids develop as they do, neither of them really getting educated on how to deal with the early age harassment of their children makes you feel displeasure over them; Secondly, Kei's way of dealing with trauma is the most unhealthy one, this making you really think of him as a horrible person. You can justify why did he turn out to be that way, yet not his actions; Thirdly, Yui's way of coping with the situation came in handed due to his parents not tending him as they should have, he never saw what was wrong with all that happened and that lead him the same way Kei went for, except that Yui was able to find his pervert and go back into his life unlike Kei; In the end, the psychology of this manga is really fucked up. The morals conflict within each other (Parents negligence, pedophilia, "pure" love) and that's what makes you not being able to determine whether this is a 'happy' ending or a twisted ending, thus fulfilling it's purpose of dwelling and poking at one's mind regarding the plot.
Magi - Tengoku no Kuchi no Naka (Doujinshi)