Sangwoo is seemingly making some mistakes. The hair, leaving evidence of Bum in his house ...

Well realistically speaking, they're not mistakes per se. Seungbae is kinda driven by his manifesting obsession with Sangwoo. But perhaps it's a good thing because it had more or less directs him to Sangwoo, but they are not solid evidences; they are unfounded. And it'll be hard fought defending these "evidences" what with how incompetent and lax Seungbae's subordinates are.

sangwoo wouldn't be so careless to allow small mistakes to affect his plan that easily, at least not the obvious mistakes.

He's had his own fair share of recklessness (i.e. black box video), but CH23 has proven that Sangwoo's a pretty smart guy. Perhaps even smarter than Seungbae given the circumstances that has been presented in CH23. Seungbae pretty much, at best, has hunches. No concrete evidence.

somehow i think it is on purpose, because basically he wasn't the killer of Jieun, it was Bum so... idk i kind of feel the apple was left on purpose or idk tbh im expecting everything ┑(￣Д ￣)┍

he tend to be impulsive, but he learned from his mistake and move on.

Possibly, or at least I hope that's not the case. Sangwoo's gone to elaborate measures to sew Yoon Bum into his life. If anything, I fear for Seungbae.

I just realized something, since Bum IS the one responsible for Jieun (he's even now paranoid af as seen in prior chapters). Then it's strongly possible that Bum will lie with him and for him; cover up their tracks. (...and set traps for seungbae (?) just imagine bum playing victim and manipulating seung bae lol)

Learned from his mistake?

I think it's when he lose his composure and beat up bum?

He lost his composure because Yoon Bum's response is not what he had anticipated at all. In my opinion, I think Sangwoo had expected Yoon Bum to feel gratitude for what he had planned, quite elaborately, for him. That's why he got pissed. But regarding his mistakes, I think Sangwoo's biggest fuck up is with the black box that Seungbae got from him.

The black box cam is in his car, and Sangwoo transports the corpses via his car. As far as mistakes go, that's the strongest one.

Just because he did a good job keeping his anonymity doesn't mean he won't be caught. It can't be ignored that Seungbae is very much on his trail. And if he does catch Bum, it'd be very easy for him to connect Sangwoo given that Bum was at his house that first time, which Seungbae remembers very well. The black box video would be easier to understand once Bum is caught as well. Seungbae investigated for a single day and basically had it figured out, but could not get the evidence to prove it. It's not that Sangwoo is or isn't smart. The problem is that no one ever considered him a suspect or even capable of doing such horrible things.

I never implied that Sangwoo wont be caught. Seungbae is keeping up, but what he considers as evidences are practically hunches. They aren't very solid and founded to be used for condemnation. As far as Yoon Bum is concerned, Seungbae considers him a victim (at least that is what was implied in the latest chapter). Yoon Bum knew he is responsible for Jieun, more than that, Sangwoo has him wrapped around his finger. Given that evidences against Sangwoo are weak and given the assumption that Bum would side and lie with Sangwoo, then it's possible that they both might out-maneuver Seungbae, and Sangwoo would be more alert and catious as ever. But like I have said in the previous comment, the black box cam is the strongest evidence (given that it had recorded Sangwoo dumping/disposing corpses, if not, then by long shot, Sangwoo would be charged with domestic violence)

Basically, everything relies upon who's side Yoon Bum would take.

Hunches that happen to be actually correct. I don't think readers given Seungbae enough credit. He figured out the entire situation in a day. That's huge. Finding evidence to prove it will be another matter entirely, but Seungbae will probably be soloing this entire investigation anyway so evidence or not, he's easily understanding the way Sangwoo works. I am not sure whether his sense of justice will outweigh his need to take down Sangwoo in the long run so he might not even go by the book later on anyway.

My point was that if he caught Bum within the next few days, the only way to convict Bum would be to find the body. Bum could confess to protect Sangwoo, but without the body it would be hard to say Bum was telling the truth. If he disclosed the body's location, they would find the apple that Sangwoo bit unless they show him moving it in Ch24. Hell, even without the apple, it'd be pretty easy to connect Sangwoo to the murder. They'd clearly want to investigate the area around the gravesite, which would mean they'd question the woman at the hotel who saw Sangwoo carrying someone that was unresponsive. You could easily guess it was the body rather than Bum once you know Bun was someone involved in disposing of a dead body. Unlike the bar, that woman got up close and personal with Sangwoo so I figure she'd remember his face. It's not like that hotel gets many customers as is.

Quite the opposite actually, I think a number of people in the fandom gives him too much credit. He pieced two and two together based on guesses, induced by his flowering obsession with Sangwoo. If anything, I'd say he's incredibly lucky but not as smart as I have originally thought. But yeah, sure, the ends justifies the means, I guess.

Anyway, I insist in thinking that he percieves Bum as the victim still. It might take a while until he figures out that he's a potential suspect, I always imagine that it might be too late if he ever does find out what he did. Bum could potentially manipulate him from there by playing victim. I actually do see Seungbae discovering the gravesite, albeit alone. Which is pretty risky altogether, there are two murderers, and he suspects there's only one. The discovery of the gravesite still seems to be a little far fetch, unless there is footage in the black box cam wherein Sangwoo makes several trips there, or unless Seungbae somehow manages to track them down there. I'm a skeptic with the whole apple thing ever since theories about it surfaced. It may be used as evidence, sure. But it might have gone rotten by the time they find it; if they find it. These are just my predictions though.

That's why I said he would have to have caught Bum or Sangwoo somehow within the next few days (unlikely), but either way, the hotel is greater evidence than the apple. If he caught Bum on the murder charge, I doubt he'd be seen as a victim anymore. The domestic abuse issue isn't going to hold up. And Bum has a history that could definitely be used to paint him as a murder rather than a victim.

I also don't think Bum has it in him to play the victim. His acting skills don't seem to be that good. He may not want to answer questions, but I doubt he'd be able to "protect" Sangwoo like that. I could see Bum killing Seungbae to help Sangwoo, but that's about it. Tbh, Seungbae dying seems like the most likely outcome.

My point in bringing up the apple isn't really about whether or not it'd become evidence. It just shows that Sangwoo isn't really thinking about tying up all lose ends, which is "odd" given how thorough he's been in the past. Bum messes up his pace and as Sangwoo becomes more and more obsessed with him, he may make bigger mistakes. I don't really see KS going longer that three seasons, and it can only end in so many ways.

yes, and when sangwoo force the head of bum to the corpses, the hair from bum will left behind too