"The heartbeat I just heard, Go Eun-hyeok's flushed face,
It makes me want to question the system.
Maybe I too am a being who can be loved."

When Soo-ae's feelings do not change despite a confrontational operation with Eun-hyeok, the unidentified system administrator gives her a final deadline, putting Soo-ae's life on the line.
Soo-ae gets deeper into the conflict with Eun-hyuk to avoid death.
As their time together increases, their feelings for each other grow stronger, and Soo-ae, who is convinced of Eun-hyuk's sincerity towards her, begins to doubt the system for the first time.
Meanwhile, Do-hwa, who accidentally gets trapped in school with Soo-ae late at night, opens her heart to Soo-ae by revealing her secrets in the darkness, and without realizing it, she begins to slowly seep into her...