Nobody talks about this one. That needs to stop. Tokyogurashi! exists in that perfect liminal space where a joke becomes something real the moment you watch it. The parody opening commits so hard to selling a fake series that it accidentally becomes more honest about what Gakkougurashi! actually is than the original ever manages. It takes five minutes and an April Fool's prank to do what a full series struggles with: the gap between cute girls and the darkness underneath them feels lived-in instead of manufactured. The animation knows exactly how disposable it's supposed to be, which is why it matters.
A parody opening for a spin-off of Gakkougurashi!, starring the characters from the visual novel Tokyo Necro by Nitro+. The animation was released by Nitro+ as an April Fool's prank, complete with an official website announcing a full TV series. The website was closed shortly after.