It’s as good as I remember it being in high school 😂 
Prince Vald takes up a cursed sword to defend his kingdom, then is exiled and goes on a quest to break his curse. He seeks out the sorcerer Halvir, who agrees to help him out of curiosity. Vald turns into his demon self at night, and let me tell you, they start fucking *immediately *. Gotta give the demon release to keep the beast in check I guess. Glaring consent issues aside, this is a Yaoi classic. It’s got way more plot than your average BL, the art is great, and it’s frequently hilarious. Vald starts developing feelings for Havi, but doesn’t yet know what him and his demon self get up to at night. I don’t remember how they resolve that but I’ll have to read more and find out. 
Oh, and there’s a bonus chapter with tentacles. Because why not.