Secrets (Underswap!GasterBlaster!Sans fic)

This is a GasterBlaster!Underswap!Sans fic in the world of Underswap. Sans (or Blueberry) is a ten-year-old skeleton who isn't allowed to leave home. While his father (Gaster) does his job at a local party store, Papyrus is in charge of making sure his little brother stays safe and at home. But while Papyrus was out getting food, and unexpected visit came to their house, making the curious Sans, follow her and find out something that he had never saw in himself. I don't own Underswap or Undertale. Neither do I own the Gaster Blaster Sans AU. Hope you like it anyway! ^^