Na-ho, a senior in high school, feels free for a short time after taking the CSAT.
However, for a moment, Na-ho, who was considering a photo to submit to the photography section of the Baekhyun Arts Festival as a stepping stone to his dream of becoming a photographer, meets an older woman named Eun-semi in the silver grass field he overheard. Na-ho, who is shaken from the moment he first met her, feels a strange sense of glee from Semi.
Eventually, Naho blindly follows Semi and asks Semi for a favor.

• "Sister, please be my model."
• "Are you trying to seduce me?"
  Why is that happening?
  Maybe it will stimulate your nostalgia
  Maybe it'll be your new pleasure
  A Korean romance fantasy that continues the tradition of 22 years of dating simulation.
  Now, let's start the story.