It’s been awhile since I watched Dragon Maid but I don’t recall that happening with her, maybe I blacked it out. Well there was the other child that was obsessed with her, I just don’t remember anything sexual. I do know that the relationship between the older big tiddy dragon and that boy feels innapropriate. I remembered while writing there is another child dragon with what I would describe as “bodankahonkaroos”. Maybe you’re right. I also think I recall the mangaka making porn of their characters to boost popularity.

Anime can have relationships between minors without oversexualization, even if that is what the characters are feeling.