First, I don't care about the age gap. It's whatever really. Second, damn those melons. Third, Mika as a student helped in a daycare, he wasn't a teacher at that point. Fourth, Mika didn't raise Natsuki, Mika was only around him during kindergarten. Natsuki then stuck around occasionally going out with Mika. Some may find it weird, but it's meh at worst for me and woooooooo at best ლ(´ڡ`ლ)