Whether Kim Rok Soo or Cale Henituse, I'm the same person. That person has just changed on the inside over the years because—

[ Because I'm not alone anymore, he realizes. ]

...Haaah.

Because people naturally change over time. The 'you' of now is different than the 'you' from when you were a little kid. And the future 'you' will be different than the current 'you'.