Looking for a manga T-T

I read it before,, but it looks like I didn't save it,, It's a Omegaverse BL where the seme is a beta, and meets an omega in heat..? Anywho, they do the sexc multiple times, and proceed to fall in love yada yada. But after they finished doing the sexc at the seme's house, the "omega" was said something like "You're mine" whilst the seme was asleep, turns out the omega was actually a semi yandere alpha that justs likes doing it. Anyone remember it?