
If you read the novel, they have one season about everything happens but from Ido perspective. Ido actually scare to be near Sejin because Ido can sense Sejin feeling. Sejin scare of Ido to the point of panic attack
This is the chapter
https://booktoki468.com/novel/5608484?book=BL%2FGL

Really agreeing with you on this. Because when early chapters start Ido has so much knowledge about sejin and I was sure they had a deeper bond or something but no they only had fleeting talks and even if Ido had remembered everything from them then he still wouldn't have known all the details ( I don't know I don't have that much faith in him) but your theory aligns well with how Ido came to know that much about sejin.

No imagine he remembered everything to the point of protecting their timeline to meet sejin the way he did -id be hella impatient looking for sejin starting at childhood lol I also thought it was unfair only ido remembered and not sejin but now looking back that was his cross to bare and his karma to pay
It says here that Bonding (whether forced it mutual) will create a connection that allows emotions to be shared between partners, even just a glimpse or a gut feeling if not the entire depth of the emotion.
I feel like Ido avoided Sejin because he only understood the gravity of Sejin's self-loathing, hopelessness, and depression after the bonding? I think being bombarded by that extremely heavy, suicidal, and hateful emotions surged and broke through Ido's psyche he physically had to separate himself from Sejin.
On the other hand, I think Sejin was so psychologicallly challenged and damaged that he couldn't even recognize nor pick up even the smallest signal of Ido's emotions. Sejin was so far gone that the only thing he recognized was the Bonding as a shackle?
Because that's the only logical thing I could hypothesize in why Ido had that odd expression right after the forced bonding and why he kept a guard on Sejin after he physically separated from Sejin. I think I do had some sort of inkling of a thought that Sejin was so close to breaking point he needed a guard? And when Sejin was really going to kill himself (basically the moment you decide on definitely suicide), there is a whole different wavelength of emotion that courses through your mind that might've triggered a fight or flight response on Ido which is why he arrived there right at the exact moment?
Like, sure, for the sake of plot Ido was just very conveniently around despite the continuous days of never showing his face in front of Sejin. And somehow he conveniently arrived while Sejin was there about to kill himself? I definitely think If had a feeling Sejin was going to "Cut Off" basically the emotional signal of the bond just flatlined.
Not defending Ido or anything, I just thing that I do being bombed with that depressive and hateful emotions would be an interesting plot detail if ever that was the case, because it would match with Sejin who is absolutely detached from his own emotions at this point, so blinded by the desire to die, that he couldn't recognize what he feels or what his partner feels (via the bond).
Or, better yet, Sejin might have even recognized Ido's feelings (which have been influenced by Sejin's depression), but because Sejin is so psychologically damaged that he probably recognized Ido's confusion and growing self-hatred as Sejin's /own inflated self-loathing/. Because, again, I think that would be an interesting plot detail since it was already mentioned prior that the bonding shares emotions/memories.
Whatever Ido had felt, Sejin recognized as his own hatred speaking volumes to himself.
Anyways. Well. I was writing this and suddenly the rope teleported to my neck /joking. I can't wait for the this manhwa's chapters always, it's so good. I really love a good angst and my favorites are when ukes (or the seme, not picky) actually succeed in killing themselves (or make a really damaging attempt).
If anyone has recommendations for other manhwas where the uke/seme kills themselves, please let me know I really love those works especially if it is super angsty, like downright heart wrenching and tragic and traumatizing. Thank you!