emotionless could be a bit too overboard, but let me explain it like this.
I'd love yaoi recommendations where the uke is either
serious, calm in an unsettling manner, hateful, cold, evil, mature, smart or just all of it
a few examples would be the cold, slightly evil uke in https://www.mangaupdates.com/series.html?id=61272
or the hotheated, cold and hateful uke in in https://www.mangaupdates.com/series.html?id=103146

I know there are more uke's at the tip of my tongue, but I hope you know what I mean <:
I'm also pretty picky when it comes to art because I don't like when the uke looks super girly with big eyes D:<

thank you~

http://www.smackjeeves.com/comicprofile.php?id=135230
yaoi webcomic ._.

Not evil, but the uke in Sayonara, Itoshi no My Friend is distant and cold, until he warms up to the seme. It takes him awhile to acknowledge their friendship at first.

In fact, there is an Expressionless Protagonist tag you might like. That link is only filtered for yaoi. There are also Indifferent Protagonist and Anti-Social Protagonist tags too.