MAGICAL GIRL SITE

Asagiri Aya is a young girl who has fallen victim to bullies at her school. Looking for a way to escape her troubles, she looks to the internet for distraction, when a mysterious website called "Magical Girl Site" appears. Simply viewing the page is all it takes to hurtle Aya headlong into the deadly world of the Magical Girl Apocalypse. There, it’s fight or die, against a seemingly endless array of savagely adorable, frilly-skirted killing machines, each armed with magical powers and an unquenchable thirst for blood and chaos. (Source: Seven Seas Entertainment) — Description from AniList community (anilist.co).