Aer is the teenage son of Mister Aer. He meets Kaehl and Selda while they are looking for Father. When he walks through the halls he speaks with a very strange, almost imbecilic kind of "slang" that Kaehl, a long-time well-dweller, can hardly understand. In spite of this, Aer is a very powerful and intelligent individual with political machinations regarding Serrin and Light Globes.
Aer is responsible sort of the "people person" of the father-son team. He is responsible for negotiation, sales, and political maneuver, while his father has more direct responsibility for globe research and production.
Aer tries to develop weapons technology in secret, planning to sell the tech to both Alizon and Serrin. This plan fails when he is kidnapped by agents of Serrin, his tech is stolen, and he is forced to work for Serrin directly. He is eventually rescued by Alizon soldiers and is instrumental in saving the country from a Serrin missile attack. He is sent to an Alizon prison following the attack.
The author has stated that Aer's name symbolizes pride and greed. Air is empty.
- Appendix, Welltower Names and Symbolism