Looking for a yaoi I read a looong Time ago

Hello falks ! Maybe you Can help me !

I juste remembered a yaoi I used to read when I was younger. I think its chinese or something, and kinda old. The MC is a black haired prince or idk, ennemy of the ML who is a blond king and who kill his family and make the MC his slave. He bullies him but they eventually fall in love. I remember the MC taking poison or something. The art is not very beautiful and they have very long and wavy hair lmao.

Thanks you all !(๑•ㅂ•)و✧