Donovan's Dread - A Wizard Did it (Patreon)

Donovan made the unwise mistake of making fun of a kid's witch's costume. Unfortunately, because he's a bad luck magnet, he just so happened to have run into an actual child witch. The boy, now angered, used his magic transform Donovan's Batman outfit into that of a sissy baby outfit, complete with a pink Dora the Explorer diaper.

Now he was to trick or treat like this. Hopefully, people thought it'd be funny and ironic not funny and humiliating for him.