Onipan!  

おにぱん！

Three young women who gain human form through the power of an "onipan" (a combination of "oni," a type of mischievous spirit in Japanese folklore, and "pantsu," a term for underwear) to help bridge the gap between humans and oni. To accomplish their mission, they attend a regular Tokyo high school while also working to improve their image by participating in community events and sometimes even becoming popular idols.