So just regular D&D then

Children can be amazingly cute and charming. They can also be vicious, sociopathic, and downright creepy because they haven't developed checks and restrictions that come with morals and general education about what is and isn't acceptable.

Sometimes they'll do both, and commit heinous acts of brutal genocide for cute reasons and in a way that makes you want to just say "awww."

Reminds me of the time I ran Descent into Avernus and my party conversed with Jander Sunstar, a vampire, long and hard enough that I didn't have the heart to make him turn into dust as the module said. He was freed and pledged his loyalty to the party. I had him show up a couple times to do cool vampire things to the party's love and awe. It just reinforces my belief that Rule of Cool is above all. We're all 9 year olds at heart.

You've reminded me of a similar experience I had, but the kids weren't mine and their parents were in the room.

Oh yeah, and the "war crime" was burning a dozen cops to death with a white phosphorus bomb.