The imprint I guess. It affect physically the alpha (Kloff with his mood swings and instability) but I'm sure that also made Aeroc so irrational in the first life and so weak to Kloff in his second
Until his end, the blonde guy kept thinking he was atoning for his sins and the reason the brunette guy turned cruel was because of his actions in the past life. So, that's why initially in round 2, if not getting his love, he wanted to atleast let the brunette be. I guess he cannot resist himself when things are going so well, as he imagined in the first life.
I m sure second timeline kloff is someone else cuz in 3rd timeline kloff was suffering cuz he imprinted this aerock and not his world one is someone else. That's why 3rd timeline is full of suffering of kloff he is away from him og omega aerock and which is unbearable for him and he grovel a lot.
What first life, bro he hurt you so much how could you remember everything and still choose to be attracted to him in next life too,is love really stupid and blind?