It's a yaoi where the Mc has ox/cow characteristics and he meets a dragon or something when he's a kid, and he is then prepared his whole life to be sacrificed to the dragon/thing by eating well and being "juicy". Thry end up grtting together kinda? It is a yaoi and has smut, and I'm pretty sure it's a manga in black and white? It is also short...please I've been searching and couldn't find anything T~T
THIS IS SO UNDERRATED I LOVE IT AND THE ANIME TOO!