@grom Most of human history has had weirder shit. Monogomy is technically the 'weird' behavior if you consider humanity as a whole.
While I would also be disgusted in that situation, there were better ways to deal with it than running away. Especially after finding out Gizel was happy. Leaving like that is just being a selfish dick, not being smart.
He should have confronted it, not just panicked. It makes less sense that he would be this stupid. He supposedly has the wisdom of his previous life. No one that mental age would suddenly act this stupid.
I question if Gizel can really be considered yandere. He essentially created this situation by behaving this way. Odds are if he had at least tried to talk to Gizel instead of fleeing like a moron, she wouldn't have had such an emotional backlash.