This information is in the thread of Project 115 - A New Threat

"Before I begin, this story isn't to start any drama to roam around this thread or anywhere else. It's meant to clear the story up so people can see how everything fits in.''
When I was 5 years old, I was bullied at an elementary school by another student in a higher grade level. I'll call him Christian, as I am not going to use his real name. Anyways, he used his friends to try and see how emotions can change and how fast can they change. He decided to call me "T115" and later named his whole experimentation "Project 115" (Where I got the mod name from). I was feeling very uncomfortable and couldn't focus in class. 3 months later, Christian was caught treating me incorrectly and was expelled from the school. As a sight of relief, I thought never seeing him again would fix my problems. Every day, it felt like Christian was chasing after me (At this point, Project 115 - A New Threat takes place), even from my thoughts of killing him today, he kept on coming. Waves of disturbing variants of Christian never stopped coming. When I failed to stay strong, I break down into tears. Christian defeats me in my mind (When you die in game: both mods).

As the years went by, it was hard being the person I was supposed to be; a loving, kind, and generous person (Which I am today). On September 17, 2014, I was in a relationship with Cold Empress (As seen in the credits of Project 115 [The first mod]). My days with her felt like everything from my past blew away and I never have had to worry thinking about Christian. But it didn't end there. Cold Empress felt sorry of what happened to me in the past. On October 16, 2014, I was diagnosed with depression. I was in complete utter shock about this (Nuketown Zombies). Continuing with my life, I had a harder time focusing on my classes, Christian never left my mind. I continue to run around my mind, but it was hard to escape and I never wanted to fall (Die Rise). I continue to run and finish the puzzles to escape my nightmares (Mob of the Dead and Buried). 

On December 2, 2014, my relationship with Cold Empress ended. She didn't care for me anymore as she didn't want to deal with my depression. I was in complete rage and never wanted to see her ever again (Claustrophobic Feelings Easter Egg). My passion for her was ruined. Since her isolation from me, I began to focus how I can escape this sadness that took over me. I talked to friends that have successfully escaped depression to see what I can do. I followed their steps and and it became a lot easier to fight against Christian (West Washington Exo-Suit Factory). I escaped the first trap and now I was facing against everything at once (The Final Stand). I continue to fight through the masses of never ending nightmares and solved the puzzle. I was later face to face with depression (Final Boss). I was ready to defeat what disorder what keeping me down for all these years. I was successful in defeating depression on my own.

As I regained my happiness, I continued life as normal. But some days I asked myself, where is Christian today? I go to my old elementary school to see if they have student records from past enrollments. Surprisingly enough, they had his address. I go to that address and find his house. I wasn't sure if I was ready to face the person that did everything bad to me in the past. As I press the door bell, I wait patiently for an answer and the door opens and I find Christian staring at me, not breaking eye contact for a good 30 seconds (Origins Easter Egg).

''Now with the EndGame update coming, here are the last days of Christian and you get to experience the argument in the update."