Mercedes von Martritz is a playable character who appears in Fire Emblem: Three Houses. She is a student at the Officers Academy and a member of the Blue Lions. She possesses a minor Crest of Lamine. She is 22 years old at the start of the game.
Mercedes is a kind girl who watches her surroundings closely and can't ignore people in need. She's also a very religious person, having spent much of her youth in a church, and enjoys praying.