I don't know bro
Is it Author maybe has kinda fetish of bad/slut girl ?? Then for the man. He eats second girl in beggining chapter, then branch manager (she was kinda slut, have many man on past), then one-night standing of prince's secretary. After, there was a vampire girl who has charm power. Do you know right, what function of charm power ?! Yepp she was a bitch too. And then, now we are showed hostest girl (dark-night job). If i'm author, i'd just use her [hostest girl] as moral story not as MC's wife.
Note : Actually, i've already many complaints since long but this is the first complaints i've written. Not only this story, many manga outside are like this.
Weeelllllllll, but this is Japan now. A country with many atheists. I don't expect much from them, if they have or know principal and method of relationship and marriage.