Magical Princess Miracle Berry

Aliens have taken over the school, aiming to drain "Miracle Energy" straight out of human breasts to power their invasion. Rumi Ikemori answers by transforming into Magical Princess Miracle Berry, turning the tables on the invaders with the same energy they came to steal.

The plot is straightforward magical-girl setup: alien occupation, captured classmates reduced to livestock, and a lone transformed heroine trying to fight her way through the school to get them back. Corruption and mind control complicate the rescue, since not every student wants saving once the aliens are through with them, and tentacled monsters guard what Rumi's after.

Play centers on Rumi's transformations and battles against the school's new occupants, pushing forward through corrupted classmates and monstrous defenders to reclaim the building room by room. It's a fixed story rather than an open sandbox, told through 2D scenes with the usual RPGM structure underneath.