I had another idea that was a bit more properly spooky, but since I ended up not making a single spooky thing for all of Goretober you instead get this cuteness. It’s a batfluff so it counts as Halloween-related!
New headcanon: Batfluffies (especially the blood-drinking ones) aren’t as afraid of water if it’s red because then it looks yummy, so you can use red bath bombs to ensure a calm and happy batfluff. Although, judging from all the staining, this is not a red bath bomb.