@lumpur as a chevalier, or if you're into younger girls buying 4 tickets to see a good movie twice with her is not uncommon for the guy.
On the other hand these 2 are practically married and the waifu NTRs the husband with the with the hypnotised husband who doesn't know what he's doing, only that his girl might get impregnated by lewd handholding without his knowledge. When the paternity question rolls around Sakurako will just be like:
I just can't get behind the hypnotism. She hasn't forced him to do anything bad yet and I'm all for pushing hesitant characters like him to take action, but not like this.