When Haruka Harukaze, a Strain that aimlessly wanders Shizume City, gets chased by SCEPTER 4, she ends up getting saved by none other than HOMRA, and decides to join them soon after. Will she finally learn how to control her powers? How will she get on with the other members of HOMRA? And most importantly, will she find the place to call home that she has always been looking for?