Drowning in the sorrow of a breakup and simultaneously bombarded by unbearable noise from her neighbor's flat, Si finally lost her composure and broke down. Today, she decided to act out of character and retaliate by creating even more noise in response. Just as she was about to take revenge, she received a song on her Airdrop, unexpectedly soothing her feelings of angst and hurt, momentarily calming her.

Who is this neighbor? This unexpected and exciting encounter somehow makes Si forget her horrible mood and the noisy surroundings. She becomes determined to secretly find out who this neighbor is.