Merielle Sim Omui is a supporting character in the anime Loner Life in Another World. She is the daughter of the border lord of Omui and is known by the epithet the Twin-Sword Princess. While she presents a capable and composed exterior as a fighter, she is secretly a tearful and somewhat scatterbrained individual. Her personality contrasts with her skilled combat reputation, as she is prone to becoming flustered and emotional in certain situations. She deeply respects her father and looks up to him as a role model. Her introduction to the main protagonist, Haruka, occurs when he rescues her from an ambush. From that point forward, she becomes persistently embarrassed by his habit of addressing her with the nickname Meri-Meri, which she dislikes. Merielle wields twin swords in battle, reflecting her title. Her role in the story is that of a supporting character who interacts with Haruka and his classmates, though her development and specific abilities beyond her swordsmanship are not extensively detailed in the source material.