Mobile Suit Gundam: The Witch from Mercury

Suletta Mercury attends Asticassia School of Technology, where students settle disputes through duels, with the most skilled duelist earning Miorine Rembran's hand in marriage. As the current fiancé, Guel Jeturk, demands Miorine move in with him, Suletta objects, prompting Guel to duel her. Suletta emerges victorious, but her win is later invalidated due to suspicion of piloting a forbidden mobile suit, the GUND-ARM. This sets the stage for a rematch with higher stakes: Suletta must win again to avoid expulsion and save the Gundam Aerial.