Shounen Ai & Yaoi Edition. Well, the title is already self-explanatory. So..read them once you're ready or in the mood for sad stuff. Also, some may not be as 'beautiful' tragedy, it really depends on the person. Some may or may not have tragedy if its has open ending, some only has super dark storyline. And some which have sad/depressive vibes but with beautiful happy ending. These mangas really hard to organize and judge since this list is pretty much a spoiler in itself.
