I can see why people are annoyed about this chapter…

It’s definitely missing the oomph from the novel.
I feel like the stakes aren’t very high in the manhwa. There was a very good description of the confusion and desperation he didn’t even know he was feeling until a drop of sweat fell onto Taekjoo’s face.
Except from the chapter:

He let go of the force in his hand. Then Kwon Taekjoo's body, which had been hanging in mid-air, plummeted to the floor. When he opened his damp hand, his fingertips were stained with blood. It had come from Kwon Taekjoo's neck. Zhenya looked blankly back and forth between Kwon Taekjoo collapsed at his feet and his own hand.

He had dealt with the bastard who didn't know his place and kept crawling back, so why did his mood feel so sunken? There was no longer anyone to bother him. But why. His heart, which he usually couldn't even feel beating, was now heaving rapidly and heavily.

He stared blankly at the motionless Kwon Taekjoo, then suddenly grabbed his arm and lifted it. However, only the arm lifted; Kwon Taekjoo's body remained limp. He grabbed his collar roughly and shook him violently. It was a flustered gesture. His eyes also shook without focus.

Getting no reaction from Kwon Taekjoo, he slapped his cheek. After two strikes, his cheek swelled red. The corner of his mouth even pooled with blood, perhaps from his mouth tearing inside. But still, there was no proper vital reaction.

He yanked Kwon Taekjoo's face close. Then he pressed his ear repeatedly against his nose and mouth, checking for breath. He could feel breath, but it was hard to tell if it was Kwon Taekjoo's or his own.

He laid Kwon Taekjoo back down on the floor and tore open his shirt. He pressed his ear against his bare chest, listening for a heartbeat. A faint pulse could be felt beneath the skin. But it was too weak, as if it might cease at any moment.

“He grabbed Kwon Taekjoo's jaw and forced it open. Inserting his fingers, he pressed down the tongue and cleared the airway. Then, something sliding down his face fell onto Kwon Taekjoo's forehead. It was sweat.

Zhenya froze. What was so pressing that he was suddenly drenched in sweat? His vacant eyes stared blankly, seeing nothing. He seemed profoundly shaken.

Soon, he got up from his spot. He walked unsteadily toward the half-destroyed doorway. Then, he suddenly picked up and threw the scattered fragments and furnishings around him. The room Kwon Taekjoo had painstakingly cleaned was swiftly reduced to ruins. As if his anger still wasn't appeased, he shrugged his shoulders and took ragged breaths.

For a moment, he tilted his head back and regulated his breathing. An inexplicable sense of disconnection spread throughout his entire body. It was unpleasant. His heart was still pounding wildly for no reason. Why. Just why. What was so dissatisfying?

He kicked off from his spot and went out.”

Even though I think people would have been a lot more pissed off with Zhenya than they already are if he’d slapped an unconscious Taekjoo like he did in the novel.