Years had passed, the people of Gravity Falls had moved on with their lives after the event of Weirdmageddon. All thinking that Bill Cipher is gone for good. But they were wrong.
Now freed from the Nightmare realm; Bill and his friends busy themselves by spreading Weirdmageddon to different dimensions, getting revenge on all who had helped Time Baby seal the exit from the Nightmare realm and leave them to die with the rotting dimension and having an overall having a good time.
All the while a figure watch over Bill. Never stopping or joining him, only watching. She has seen dimension fall into madness and eaten by Bill to fuel his ever growing power, those that did not completely fall into madness were spared the horror of being eaten and is instead gifted to one of Bill's other friends to do as they please.
She has never once felt bad for the dimension they landed on, nor has she needed to show herself and get her hands dirty for Bill. She admit that it can get boring but it gave her time to watch her dimension, being bounded to Bill allows her to borrow his ability to see through his many eyes and she use it to watch the Pines family grow.
She watched as Stanley and Stanford sail around the world, she watched Mabel grow out of her childishness and grow into mature fun loving woman, and lastly the youngest, Dipper. She loves watching Dipper the most, the little Pine Tree suffered from PTSD after the event of Weirdmageddon and it almost broke him countless times. He had hidden it well but it did not take his older twin to noticed and try her best to help him.
It took him years to heal even with the help of Stanford, Stanley and Mabel and grow into the man he is today. It is her fault really, she enjoys being the shadow monster when he is alone, she enjoys bringing up the pain from the scars that is hidden from their eyes. Oh how she enjoys watching him suffer but the others did not escape her.
She's the shadow of Bill that Stanford sees while they are sailing, she is the trigger that make Stanley see his true memory of Weirdmageddon that is immediately forgotten again once someone finds him and she is the voice whispering blame into Mabel's ear, blaming her brother's pain on her selfishness.
She watched as all four Pines suffer under her and yet grow stronger with each others help, it made her wonder how her life would turn out if she was allowed to grow with the love and care she sees in the Pines family. She never let herself go down that path for too long, nothing will change the past and not that she wants that. Even if Bill ignore her voice of reason he is still her beloved friend, she won't admit it but he is a brother figure to her, the only person she looked up to and she will kill anyone who tries to take him away from her.
He comforted her when she cried at the memory of all the pain, hate and betrayal she suffered before being bounded to him. He did his best to be patient during one of her fits of anger. He let his actions earn her trust instead of forcing it out of her. He's the one who is always there for her and she loves him for that.
People say he's crazy, people say he's evil. But to her he is a father, a brother, a mentor, and even without the deal they made she would still ripe apart any dimension to keep him safe and happy. After all, he saved her from falling into madness and gave her a new name, Shadow, she is his Shadow.
From now and till the end of their lives.
