I'm looking for a romance between a human and a monster BOY. The human can be a boy or a girl, the human can be any manner of humanoid race. But I'm looking for -ugly- monster men, none of this sexy demon sparkle vampire nonsense. Furries are acceptable. I suppose I could live with a semi-attractive monster if he's scary enough.
Any length welcome. Adult themes are a-ok but not required. No magically turning the monster into a human at the end and no mind control slave lovers please.

I just want to see a beast fall in genuine love with his beauty

The only example that comes to mind is Ii Orc no Hi

Hmm... I Am Currently Living with a Bear Not really, but I really liked the delivery.
Mahoutsukai no Yome and Frau Faust both by the same author, the romance is a little... You've gotta look hard to see it.. LOL
Watashi no Kairos - The Tale of Little Gladiator Technically not, but at first you get fooled... That's already a spoiler... =3=
Tobenai Washi Ouji Also a technically...
Folk Tail Tonakai Another... kinda-sorta one...
Niehime to Kemono no Ou Errrrr..... Part-human? Monster/demon king who is cursed with a sparkling human form?? He's mostly drawn in his monster form though, so... It's not complete so I don't know if he would end in his human form or not..
Skeleton Sister Well... Kinda like the previous one with the part sparkling human...
Majo to Yajuu Kinda? Maybe?
Ookami Ningen to Ningen Ookami

Ok, these aren't actually what you asked for, but they relate some.... You can try them if you want, til someone with better recs comes along. XD (Most of them are shoujo so the sparkling hot guy are... coughrequiredcough...)

Zero Kara Hajimeru Mahou no Sho - Witch and Beast

This is terrific!
It looks like my night is filling up 😀