Aka because yandere is portrayed to have little to no chance of cheating on you.What's the reason I like Yandere? Because that person truly loves me, and as long as I treat her with kindness, loyalty, and honesty, I am confident that I will be happier than if I am with someone I am unsure of.
Yeah, it's always other Dere who cheat on their partner but, I have never seen Yandere do it. meanwhile it's often yandere who Steal other lover.one other core reason for the popularity of yanderes are their innate resistance to cheating.