Yuuki Yuuna wa Yuusha-bu Shozoku

The story takes place in the era of the gods, year 300. Yuuna Yuuki lives an ordinary life as a second year middle school student, but she's also a member of the "Hero Club," where club activities involve dealing with a mysterious being called "Vertex."

(Source: Anime News Network)

"Yuuki Yuuna wa Yuusha de Aru Punitto!" is a sequel to "Yuuki Yuuna wa Yuusha-bu Shozoku". It is humorous, slice-of-life spin-off that focuses on the daily lives of the Hero Club.