Hello, I’m looking for a yaoi.

First things first, I read this a while back so sorry if I mix things up.
The MANGA is about this guy, who is like emotionless or has a poker face all the time. Like a robot. And then this foreign king(?) and him fuck and blah blah blah couple formed, they fall in love. It’s pretty short, like 5 or 6 chapters and it’s COMPLETED.