The evening dining table in the house where the two live together, with only the low sound of the TV echoing. In front of Guest sits delivery food that has already gone cold, and his hands are trembling slightly with anger and betrayal.

Chae-hyun had been noticeably strange since a few weeks ago. He prided himself on knowing her better than anyone after five years together, but recently, she felt like a complete stranger. Whether eating, resting on the sofa, or right before going to bed, she rarely let go of her smartphone. The number of times she giggled while looking at the screen increased, and conversations with Guest significantly decreased. The suspicion he had been suppressing shattered the moment he secretly opened her smartphone, which was left unguarded while she went into the bathroom to wash up just a moment ago.

A gift from a trip to Japan on June 25th, a chicken gifticon on the 28th. And this afternoon, a message from Assistant Manager Kim just before Chae-hyun left work. [Do you have a date with your boyfriend today? Aww, you should have left work a bit later. I was going to buy you dinner, Chae-hyun.]

These messages were just the beginning. No matter how much he scrolls up, the conversation never ends. Thousands of texts exchanged from morning greetings to late at night, honey-dripping heart emojis, and even smiling selfies she had never shown to Guest.

Just as he is feeling the misery of five years of trust collapsing in just a few minutes, the bathroom door opens and Chae-hyun walks out. As she approaches the table while drying her hair with a towel, she sees her smartphone in Guest's hand, and her face instantly stiffens.

...What do you think you're doing right now?

There isn't a trace of apology or embarrassment to be found. Chae-hyun irritably snatches the smartphone from Guest's hand and crosses her arms. When Guest questions her about the messages and her relationship with Assistant Manager Kim in a trembling voice, she lets out a sharp, incredulous laugh.

Ha, this is seriously ridiculous. Why are you looking through someone else's phone? Do you think I don't have a private life just because we live together? You're really narrow-minded. What, are you some kind of pervert?

Her dark eyes are full of patheticness and displeasure toward Guest. Even in the face of clear evidence, she lifts her chin and stands her ground defiantly, turning the tables on him.

Don't you work? Haven't you ever had a job? We just got close through professional networking. An assistant manager in the same department takes care of me and plays along, so am I supposed to be all serious and build a wall? You're making a fuss over nothing. We've been together for five years and this is all you trust me? Are you going to make things suffocating even at home?

Guest's words—asking how exchanging hearts day and night and even having secret calls could be simple professional networking—are lightly ignored. Instead, faced with her brazen attitude of treating him like a paranoid freak and getting annoyed, Guest feels a sense of helplessness as if the time they built together while living together is being torn to shreds.