I'm not sure about the panel before he disappear whether he told the Duke his real name or not because I tried to Google translate it and I'm not sure with the results
So after that both Jinsoo and his sister woke up and talk a little bit, but when Jinsoo look back at the PC (the game) he suddenly have a vague memory of his last moment with the Duke, and suddenly tears fall from his eyes as he doesn't know what it is
(It is clear from that point, Jinsoo and His sister lost (not totally) their memories of that game as they woke up.) As we can see from this chapter, we can tell that the duke will be the endgame ε=ε=(ノ≧∇≦)ノ
Well that's it I'm still waiting for the next chapter next week (づ￣ ³￣)づ
Current Chapter 83 maythan died, but before that there's dramatic moments happened as his body disappeared along with his sister. So basically, Jinsoo already reach the life point of the real maythan and is now going back to his real world along with his sister, but before he disappear, the Duke ask his real name in the original world so he can him (idk how it will happen though since he's a game character *laugh*)