Comment by Squid on Omniscient Reader’S Viewpoint - Chapter 188

What  basically happened, in the future(around chapter 270 in the novel), Kim Dokja makes a deal with Secretive Plotter : The constellation saves his friends in exchange for anything that the Secretive Plotter wants. Secretive Plotter sends our reader to Yoo Joonghyuk his 1863rd round, where sh** happens. Han Sooyoung made an avatar with a lot of her memories at the beginning of the scenario, and that avatar became the '1863rd' Han Sooyoung. She wants to seal Yoo Joonghyuk, so he won't regress anymore. Like an eternal sleep. Ofcourse, our regressor wanted to die, but at the last chapters of that 'arc', he creates an avatar of himself(2 Yoo Joonghyuks, one with a black coat and the other with a white one) :

'I... I want to die.' he mutters, redirecting his gaze towards me. 'I-.... I want to live.' (something along the lines of that.)

After that, he kills the avatar with the black coat, regressing. One part becomes an outer g** : The Secretive Plotter. The other regresses, and meets 'Kim Dokja'. So yes, our 3rd round is ACTUALLY the 1864th round and Secretive Plotter is the 1863rd regression Yoo Jooghyuk.

Yoo Joonghyuk is an overpowered character, with an incredibly fragile mental state of mind, due to all the trauma and death he witnessed. He distances himself from people and acts cold in fear of hurting himself, with the pain of losing someone. Ofcourse, we have 999, who was the most gentle round. It was the only round where he sacrificed his everything for his companions. Yoo Joonghyuk his character is basically : Distancing himself and building a wall around his heart to protect his sanity and feelings, which sometimes results to him coming over heartless, cruel and as a monster while he isn't.

Han Sooyoung her character is really interesting, especially around chapter 270. You see her, and her 'masterplan' to lock yoo joonghyuk forever. Like an eternal sleep. But Kim Dokja, like the rat bas**** that he is, fuc*** her plan up and fuc*** everything up.

The 1863rd han sooyoung, impressed, finishes the scenarios without yoo joonghyuk, and finally reaches the final wall, where she is also stuck. She wonders : what would Kim Dokja have done? Is he the key?, but gets interrupted by the 1863rd Dokkaebi King, who shows Kim Dokja his su!c!de attempt when he was 15. She decides to go to the 'past', to kim dokja his timeline before the apocalypse started with the help and together with the dokkaebi king, and becomes a subconsciousness in kim dokja's han sooyoung. She writes and posts TWSA for over 10 years, without letting kdj's han sooyoung know. 

Her character is based on the fact that she doesn't know she cares a lot about dokja, even before she actually met met him. After 1863rd hsy her consciousness faded, the dokkaebi king continued uploading for her, and later turned into the 4th wall to protect dokja. Hsy eventually gets the memories from the 1863rd turn back and with that extra knowledge, does everything to bring dokja back after he became the oldest dream. 

She has a snarky, smart and sneaky personality, yet an incredibly complex and caring one towards kim dokja.

i hope this was fine, i'm still gonna read the side-story, than i can give more info ^^

I will find you and feed you to my Cupcake. Don't underestimate her, she's a lil hungyy 😐.