Kill the Demon! Starting from Inheriting Tens of Billions of Inheritance

"Miss Tang family! Can you just take out several hundred million from your pocket?" "The eldest lady of the Tang family needs to eat, feed her!" Because of the decline of his family, Tang You has been living in the ridicule of a group of people since he was a child until one day. "Miss, this is the inheritance left to you by your grandfather, totaling 90 billion." The lawyer handed Tang You a bank card and a stack of documents. "What?! How come my grandfather has so much inheritance?" Tang You couldn't believe it. In her eyes, her grandfather was a bad old man who loved to collect useless antiques and thus ruined her parents' inheritance. "Your grandpa is very capable! In addition, your grandpa hopes that you will inherit his mantle and become a very powerful demon slayer." The great demon Hongyue suddenly appeared, "For your grandfather's wish, I will try my best to help you." Tang You was confused. How did it feel to suddenly learn that his grandfather, who had been poor for more than ten years, was a billionaire + a demon slayer?