Ryu Lion is a former adventurer and a waitress at the Hostess of Fertility in the anime series 'Dungeon ni Deai wo Motomeru no wa Machigatteiru Darou ka', also known as 'Is It Wrong to Try to Pick Up Girls in a Dungeon?'. She is known for her calm and composed demeanor, concealing a mysterious past. Once a member of the Astraea Familia, Ryu is skilled in combat and possesses a strong sense of justice. Her character adds depth to the series, often playing a supportive role to the protagonist, Bell Cranel, and his journey through the dungeons.