basically MC's sister and father end up playing major roles in his decision to basically go back into time before gates started appearing and basically go and defeat every monster that was heading to Earth so that no one aside from himself would have to remember or experience all the horrors that happened when gates started appearing and so that he could restore what was lost against the army of the chaos world even though he would have been praised as a hero if he let everyone remember what happened, but be even went so far as trying to keep what happened a secret when he was asked by the chief of the monitoring division when he felt there was something important that he couldn't remember and didn't reveal to Cha Hae when she wanted to know how they were connected and why he felt familiar, which when they were dating in the side story at the end she made a bet with him since they were both in track that if she beat him in a race that he would tell her how they knew each other if she ever beat him in a race and on one date she told proposed a competition and then after he accepted she told him that if he loved her then he wouldn't move from that spot and then walked to the tree that was declared the finish and she ended up being one of two people he outright told about what happened without her actually remembering, as for the other it would be the chief of the hunter association when he gave him medicine to treat his weak heart