A cadet in the training school of the Capital Guard which protects the Capital Tower. He is incredibly talented, and has skipped ahead two grades. Falling in love with Aida at first sight, Bellri ends up fighting alongside the pirates against the Capital Army. He is one of the three people able to pilot the G-Self.

A mysterious girl who suddenly appeared on the Earth in the G-Self. She loses her memory, and because she was rescued by Captain Dellensen of the Capital Guard on a Monday, she is named after that day. She is one of the three people able to pilot the G-Self.

A girl who has joined the Amerian pirates. Aida joins an operation to steal Photon Batteries with the G-Self which came from Raraiya. The operation fails however, and she is captured by Bellri. She uses the alias Aida Rayhunton when captured, but there is a secret behind her origins.

A mysterious mobile suit not belonging to any known country. It only activates under specific conditions, and Bellri, Aida and Raraiya are the only ones who can pilot it. It is a generalized mobile suit that can deal with various situations by equipping various types of backpacks. The G-Self's color also changes depending on the backpack used.

A flight mobile suit used by the Capital Army. It has gigantic wings on its back and can fly when they are spread.

A mass production mobile suit used by the Pirates.