Responses
Oh wait I have that in my still reading list, will come back when I find it.
Oh here it is!
I think it’s Two Empires, The Slave Of The Empire (Yaoi)
THANK YOUUU ヾ(☆▽☆)
it's a bl manhwa, the uke was a king then reincarnated as a slave (blond), he is also a great magician, the seme was his enemy(?), seme is black haired. i remember it being toxic