Acrotrip

Synopsis

Machiko, who lives in Sakai City, Niigata Prefecture, is an otaku girl who is a big fan of the magical girl Berry Blossom who protects the city against the evil organization Fossa Magna. However, nobody was worried about the battle of the two anymore because Chroma, the wicked evil villain, was too sloppy. So Machiko decided "I want magical girls to shine brighter!" That desire leads a shy junior high school student to a strange evil path.

Synopsis & details from MangaUpdates