Nastasia is a character in the Wii video game Super Paper Mario. She is Count Bleck's right-hand minion and possesses the power to use hypnotic magic, which is most commonly used to turn allies of Mario into enemies. She is in love with Count Bleck and wants to replace Timpani as his love interest but is always denied. Apparently, she has command over Bleck's other minions, forcing O'Chunks to write an essay about Count Bleck and write and sing a song praising him as punishment for failing to stop Mario.
She is Count Bleck's only minion you don't fight in the game, as she seems to lack the ability to fight.