La Blue Girl Returns

As heir to the Miroku clan, teenage ninja Miko Mido carries the complicated responsibility of brokering peace between humans and the Shikima — a demon race with very specific appetites. That alone is a lot to manage. Now a new faction has entered the picture: the Mahoroba, a race of butterfly-demons who want to kidnap Miko and her sister to get their hands on the seal case controlling the Shikima. Their endgame is something called the Shikima Brain, a legendary place said to grant power over the entire universe. Stakes don't get much higher than that. This is a 4-episode OVA from 2001 by Arms, based on the manga, and it leans fully into its blend of supernatural action, ninja clan politics, and explicit content. The tone balances demon-realm mythology with dark humor, so it never takes itself so seriously that it becomes a slog. If you're familiar with Urotsukidōji: Legend of the Overfiend or Demon Beast Invasion, you already know the territory — this sits in that same corner of supernatural horror and eroticism, though La Blue Girl has a lighter, more action-adventure energy underneath it all. Bible Black fans looking for something with more plot threading through it might also find it interesting. It's a niche watch for sure, but within that niche it does exactly what it sets out to do.