In Fyodor Dostoevsky's novel "Crime and Punishment," Raskolnikov orders his sister, Dunya (short for Avdotya Romanovna), to do several things throughout the story. One of the key instructions he gives her is to marry Luzhin, a wealthy suitor who has proposed to her. Raskolnikov believes that Dunya's marriage to Luzhin will secure her financial future and provide a stable life for her, even though he has strong reservations about Luzhin's character.
Raskolnikov's desire for Dunya's happiness and financial security is one of the driving factors behind his actions in the novel, including his involvement in a murder and his subsequent moral struggle.