Nigatsu no Eden
Ohmygod what did I just read. I thought this would have a happy ending but no. Still it was good. An artist picks up a injured guy off the street and keeps him in his home because he becomes attached. The guy has a tattoo and he's obsessed with drawing it and sketching him. They fall in love but the boy with the tattoo can't stay because he belongs to a yakuza as his lover. He gets taken back and thats that. They think of eachother in the future but don't see each other ever again.
Chou to Kumo no Su
Prequel to Chou to Hana no Kankeisei. Boys mother dies, he becomes the replacement for her. The uncle (not related) gets possessive, raises him, never lets him leave, the older he gets the more sexual it gets. In high school the unlce tattoos a womb on his stomach so that he never leaves and becomse his 'woman' but he gets abandoned anyway. The boy grows up and is the main character from story 1 in Chou to Hana no Kankeisei
From Now On, I'm Your Dog