Cagliostro on the Water
Play as Cagliostro, the founder of alchemy. Swim cutely, use alchemy magic to stop evil bigots and their minions!
Normally it'd be cheating to use alchemy or any kind of magic at a sports event, especially if it's one run by muggles.
But if JK Rowling tries to stop her from competing with the other female athletes, she will go ahead and use it - she will protect the peace of the event from bigotry by any means necessary!
Why are there sharks in the swimming pool?
Because JKVoldemort the evil villain who goes out of her way to enforce bigotry, is not actually a muggle, even if she pretends to be one.
The goal of this is similar to Sakurako in Nightmare School except with swimming mechanics instead of the gravity stuff - you need to defeat all the enemies and clear everything out, and the enemies only shoot at you if you move in front of them based on the direction the enemies are facing (there are some new enemy varieties that deviate from this though). However you have a healthbar this time instead of instant death - and although the game will once again start out easier on the early stages and later get harder, the health difference will be factored in accordingly.