Reticence
(Book)

Percival Tunstell loves that his sister and her best friend are building themselves a family of misfits aboard their airship, the Spotted Custard. Of course, he'd never admit that he belongs among them. He's always been on the outside - dispassionate, aloof, and hatless. But accidental spies, a trip to Japan, and one smart and beautiful doctor may have him renegotiating his whole philosophy on life.