Life is a breeze, until a storm hits.
After defeating Shishitoren, the students at Furin High get a breather and bask in normal school life. After meeting some powerful classmates and astounding upperclassmen, Sakura gets elected class captain, blossoming some changes in himself. Meanwhile, a dark shadow looms over one of Sakura's classmates. To save his friends from the infamous team, KEEL, Sakura and his class jump into action!