A mysterious young man from the ship's lower levels who becomes an ace Guardian mech pilot and celebrated hero of Sidonia. He leads the fight against the Gauna alongside his friends and plays a crucial role in humanity's survival across both the initial crisis and the final battle ten years later.
Tsumugi gradually realizes her romantic feelings for Nagate during the decade of peace.
Both serve as core crew members preparing for the final battle to protect humanity.
They operate together within the Sidonia defense structure during the renewed Gauna threat.
They work in parallel roles within the Guardian mech pilot corps and ship operations.