Melusine is a fictional character from the mobile game Fate/Grand Order, part of the Fate series. In the game, she is a Lancer-class servant and is depicted as a dragon-like creature with a strong sense of loyalty and duty. Melusine is based on the legendary European water spirit of the same name, often associated with transformation and enchantment. In Fate/Grand Order, she plays a significant role in the Lostbelt storyline, showcasing her combat prowess and her complex dual nature, both as a fierce guardian and a gentle protector.