Gu Yu always felt that she had forgotten a lot of things, so she returned to her middle school as a teacher to explore the forgotten memories.
"I seem to have forgotten a very important person."
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"You will remember me, Ayu."
Purpose: Using memory as a clue, explore the forgotten emotional bonds and self-searching in the passage of time. Through Gu Yu's experience of returning to middle school, it shows human beings' obsession with "important people and unfinished things", as well as the secret traces left by memory in the gaps in time and space, suggesting that those forgotten emotions and promises will eventually re-grow and resurface in the depths of the soul in some way.