The Mansion Tower is a residential estate in the Birdmen series.
The Mansion Tower is a high-rise apartment block with potted trees and shrubbery leading to the entrance, which leads to a lobby with automated doors. Sagisawa Rei lives here along with his housekeeper on the top floor of the highest tower mansion.
The entrance to the sky terrace is usually locked after 6pm, but Rei can get the key from the concierge by way of exception. It is the usual meeting place for the Bird Club members. The sky terrace is equipped with a helipad.