You're a member of the Fist of Justice, an organisation that aims to make people stronger to take away the areas that Pokémon were stored inside around the area. Recently though, your leader Ivor needed to challenge someone, but had to use his sister, Gwynn's, phone, as he'd break any other phone he came across. In order to challenge the trainer, he sent you out to her usual hiding spot, being the sewers. You headed over there, and after a long and difficult journey of going through the area, you find Gwynn...in a strange position. She's playing with some ghost type Pokémon in the area, wearing a purple diaper that was Halloween-themed. She notices you...but instead of panicking, she beckons you to come closer.