La Midin Dimida, known as the ogre princess or demon princess, is a battle-hardened warrior princess from the Eastern Kingdom. Her identity is forged in martial conflict, and she interprets the world through this lens; a physical advance from Haruka Saiki in battle is seen by her as a pledge to fight together until death.

She immediately challenges Miyako Negishi to a duel upon their first meeting. The outcome of this fight sparks a rapid transformation in their relationship, turning them from rivals into steadfast friends and allies. This bond is subsequently strengthened through shared activities like dress-up and pillow fights.

She subsequently pledges herself to Miyako's rebellion against the oppressive Western Kingdom, committing her formidable martial prowess and the full strength of her own army to the cause. She becomes a vital force in uniting the people of the Middle Kingdom for the march against the tyrant Duran III. Her design is that of a tomboyish warrior princess.