Title help please

It's an omegaverse. Omega(uke) grew up serving the rich grandmother of the alpha (seme) when I think the grandmother died, alpha and omega got a contract to be f@ck buddies or so. The condition were 1. No knotting 2. No coitus when one of them is in heat or rut 3.If they love someone they're free to leave and 4. No falling in love with each other. Alpha find it convenient and smooth sailing being in such contract with the omega. He also find his scent smelling good. One night they accidentally knotted due to alpha's rut in which. Omega got pregnant and he left with the excuse that he love someone else. alpha thought everything was ok with the two of them and misses the omega. He later tracked where the omega lives and tried to pursued the omega to comeback kept visiting him. Later knew that omega was pregnant since he got him investigated. One scene was alpha was surprised that omega was wearing glasses.
Think that was last part that I read.
Please help （/TДT)/