Comment by Anon on Stranger Than Friends - Chapter 96

Alright , it appears as though we're dealing with some S-tier manipulation from Sihyeon and how it's began to really weigh on Dajeong emotionally.

In this case, Sihyeon began to withdraw giving attention to Dajeong, despite him knowing how the younger party felt, and then when Dajeong tried to discuss the situation, he essentially went "You're making this hard for me, you're the one who wanted this, I'm just doing what you want." Instead of being aggressive, he's playing like a victim of Dajeong's advances. This ends up making Dajeong do exactly what Sihyeon wants: he feels even worse and gives himself up to be the boss's stand in for Yi-Hyeok, if only to just be with him- note the smirk Sihyeon has after Dajeong gives himself up.

The cycle is now abuse, affection, abandon- Sihyeon uses Dajeong whenever he needs a fix (at this point in the main storyline, the boss' infatuation with Yi-Hyeok is getting stronger, but since the boss can't have him, Dajeong is the replacement), he tends to Dajeong's wounds after the fact, and then ignores him until the next time so Dajeong's always longing for him. 

On one hand, this is (partially) fulfilling Dajeong's want for attention, but on the other, because he's fully aware of Yi-Hyeok and Sihyeon's feelings towards him, we're seeing him become envious, despite likely being able to gather that Yi-Hyeok has no interest in the boss. 

We've still got some story to fill in before we reach that point where Yi-Hyeok catches them in the storage room, but dämn.

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