The Fairy (Kancolle) representation of the historic 601st Naval Air Group of the Imperial Japanese Navy.
In-game, can be obtained from remodeling the individual Unryuu (Kancolle)-class aircraft carrier trio (barring some events that gave them as stage clear rewards).
This is a reference to how the 601st NAG was originally destined to the Unryuu-class but were a shore-based formation throughout their combat history due to shortage of skilled pilots.