Foster A Prince

Hill, a girl from modern times, fell into an inspection shaft when she was absorbed in a game, only to time-travel and become a Miss Bully in the Duke's Mansion. Her ultimate mission is to help Surin, her nominal brother who's been pushing her over since little, recover his status as Crown Prince and claim the throne… However, he's not as weak and helpless as she's imagined. Rather, he's a scheming lady-killer!