The entire planet entered the ABO differentiation period overnight.
A former lover becomes an Alpha in a vulnerable period
"I'm sorry, my excellent genes still have to continue..."
"A and O are a perfect match. You should forget our past..."
The former rival turned into an Omega in the fever phase...
"Will I die if you come here and mark me?"
"I don't want anyone else, I just want your pheromones."
The kind-hearted Alpha heroine* who is cold on the outside and has just begun to fall in love* is putting on airs, and the Omega hero who is aggrieved and controlling on the inside and secretly has a crush on the heroine.
Purpose: Destiny allows us to find someone with a 100% pheromone match