That would be because Wendy has more interest in the main character than just to be childhood friends. So that's why she tells us to not date other girls than her. How this rule of hers will play in when the dating system is added in I do not know
I have a idea: When Wendy finda out we are dating someone, she tries to eat us, but the character we are dating comes Just in time and unbirth us or something like that
