Kasuga Tsubaki's the president of the Inner Discipline Club, a club found in Hyakkiyako Alliance Academy. She's notorious for being a serial sleepyhead, taking naps a lot of the times. Being a true sleepyhead, she can sleep virtually anywhere in any number of ways. Despite this, she's not defenseless as she was able to flawlessly dodge gunfire from a bunch of thugs while in deep sleep. Despite her lazy daytime habits, she engaged secretly defending Hyakkiyako at nighttime.