Seizei Ganbare! Mahou Shoujo Kurumi

Kurumi Azuchimomoyama, a normal 14-year-old girl who attends Egaogaoka Middle School. One day, an angel named "Devilun" appears before her, and grants her the power to be the beautiful magical girl dinosaur angel warrior "Prima Angel," and tells her to fight the evil "Darkness Whales" organization. She proceeds to indiscriminately take out Darkness Whales members with weapons that stink of blood.

(Source: Anime News Network)