The Letter Bees are requested by the government to go after the Cabernet, as they still consider it a serious threat. With not enough personnel, the Sub Master of the Bee Hive and now office worker, Aria Link, heads out on a delivery herself. The letter is addressed to a Houdai Franklin, who was on the airship during the Day of Flicker and experienced that terrible accident. Since it's her first delivery in a long while, Niche tags along as her dingo, but the new duo has a tough time working together.