Benimaru is the Battalion Commander of the 7th Special Fire Brigade. He has both Second and Third Generation Abilities and because of that is considered to be the strongest Fire Force member. (Source: Enen no Shouboutai Wikia)

Yuu is a first year high school student who doesn't know what it's like to have a crush. She joins the student council, where she meets Nanami. Her family owns a bookstore and lives above it.