A Marvel comics character, first appeared as an amalgam of Gwen Stacy and Deadpool created by Chris Bachalo for a variant cover of Deadpool's Secret Secret Wars #2, which was one of twenty such variant covers published due to the popularity of Spider-Gwen from June 2015. Marvel later created her as a fully-fledged character because of the popularity of the design. Her real name is Gwendolyn "Gwen" Poole. She has other codenames such as Pink Slayer.
An unemployed 18-year-old high school dropout and a comics fan who transported to the Marvel Universe from the real world, Gwen has vast meta-knowledge about the Marvel Universe and can break the fourth wall to interact with readers. She even has the ability of reality manipulation which she later used to retcon herself as a mutant.
Unlike Spider-Gwen, she's not a variant of Gwen Stacy or Deadpool.