Is it normal to pay kids to punch my girlfriend in the crotch

I've always been quite the joker, and one thing I've come to love doing is paying people - young children, to be precise - to punch my girlfriend in the crotch.

I've done this more times than I can count, but one good example was the most recent time, when we were at a mutual friend's cookout and I gave a dollar to their 5-year-old to run up and pop my girlfriend in the box from behind while she was bent over. Of course, she's quickly become wise to this little game and, as always, completely ignored the child and instead ran after me for a good minute or so before getting tired and giving up. As always, I just laughed.

Is it normal to find great joy in this? Do you think it's really as weird as many have said?

Important note: For every white knight who gives me shit like "omg you're terrible she could do so much better than some weirdo like you", I will make a point to do this again, and I'll tell her it was from you.