Take Flight, Chidori!

Hikari and her sister are off for Europe. But their plans are interrupted when the Fusou naval fleet is struck by a newly emerged Neuroi nest. It's up to Takami to defend the fleet against this unexpected threat, but she's overwhelmed by the sheer number of enemies. When she uses a dangerous technique to stave off the foes, it's up to the inexperienced and underpowered Hikari to protect the fleet...