need more info, is this omegaverse or just on a normal setting
Normal setting, they live with each other and are like 27 or 28 at the time
Ohh mb, I didn't see your comment about that it's a normal setting
I can list some manhwa/hua and manga) however, I don't think it fits the age regression and being mean to uke.
Black Lotus kinda fits but they weren't living together, they were already scheduled to marry and were around early 20s. Not 27/28. Although seme lost a good chunk of his memory.
A brown haired uke and a black haired seme are dating but something happens and the seme loses his memory of the last 7 or something years and thinks he’s 18 or 21 again (I don’t remember) and is mean to the uke who he completely forgot