Midnight

This weeks episodes confirmed what I already suspected. Hyuk is still fundamentally the same person he was 7 years ago when he killed his pregnant wife (don't get at me with the technicalities, he strangled her, then pushed her, then left her to drown and die, that's murder). Hyuk has in fact been a remarkably consistent character from the start of the show until now. Nearly every other character has changed, but not him. He's always been a nice person on the surface until he's not. He was nice to his wife until he thought she cheated on him. He was nice to Yura until he thought she betrayed him. He was nice to Wang Shik until he thinks he's in love with Sunny. And he will be nice to Sunny only until he thinks she's loyal to him. And even when he's nice, he's really only "nice", he still has moments where he shows what a creepy, possessive jerk he is, such as just this episode where he goes through Sunny's room without permission, looks at and then steals her diary. He had a shit childhood but that doesn't prevent him from knowing right and wrong. Like a true psychopath he knows right and wrong and just doesn't care. He only starts to feel guilt when he realizes that he made some wrong assumption, like finding out his wife didn't cheat on him.

Nope he's still a murderer. What he did to his wife showed that he was more than capable of murder and she was very lucky being so pregnant to have almost gotten out of the water on her own. What if she wasn't able to get out herself and drowned after he pushed her in? That was a likely scenario and he knew it when he left her even after she called out to him for help. It was at the very least attempted murder and he put her in a situation that the real murderer took advantage of. He was okay with her dying. That's a murderer in my eyes. Same thing with Wang Shik's mother. He didn't check if she was dead, remember she wasn't and presumably died later of blood loss. She might have survived had he called emergency services. Instead he shows no remorse at killing a women by accident seeing it only as an inconvenient troublesome thing for him. Then he tries to cover it all up, which includes ordering WS dead. So that's another attempted murder. He is not redeemable. There is nothing to suggest he wouldn't snap at Sunny like he did with his first wife if she ever made him jealous or betrayed him. In fact he's already shown to be very possessive over her look at his response to WS's "confession".

It makes no difference whether he directly killed her or not. He left her to drown even after she called out to him for help. She was 9 months pregnant and wearing a heavy hanbok, meaning it was highly likely she couldn't help herself out of the water. He didn't care, he was okay with her dying in that moment so he left. It's still attempted murder at the very least.