I have this theory about Jung's behavior, which resembles that of a parent stemming from his parent complex. This complex is rooted in his upbringing, particularly his father's parenting style.

In Season 1, Jung's behavior towards Seol and Inho near her house sparked this idea. His actions resembled those of a parent trying to subdue their anger and calmly handle a situation. This behavior is consistent with someone who has never been taught to process negative emotions like anger.I didn't think too much of this idea back then but my support for this idea only got stronger as the manhwa went one.

We see enough of Jung-seol conflicts to draw upon two conclusions. One being how jung turns to isolation, he could either expect Seol to figure out the reason why he got mad or he was never taught to process the emotion so did it mean his isolation tendencies could provide him some time so that he could no longer be affected by what pissed him off in the first place?

Through flashbacks in Season 3, we see Jung's childhood and his father's parenting style. It becomes clear that his father valued only positive emotions and discouraged Jung from expressing negative ones. This upbringing led Jung to develop a coping mechanism where he controls situations by controlling people when needed. However such negative emotions are cannot be avoided so this coping mechanism Jung had wouldn't help in every way possible so now his upbringing comes into the picture.

As a result of his father's parenting, Jung often reacts like a parent, subduing his emotions to avoid conflict and be the bigger person. This behavior is evident in his interactions with Seol, where he uses a parental tone and mannerisms to console her.

In an ideal parent-child relationship, parents help their children process negative emotions. However, Jung's father did not provide this kind of emotional support. Instead, Jung learned to suppress his emotions, leading to a sense of isolation.

I would say Jung's tendency to let go of negative emotion is a result of his father's ubringing and his isolation tendencies resemble his mother's who was very much aware of her husband's parenting but chose to ignore it by keeping her distance with jung due to her job and few other reasons I am not quite sure of.

Jung was taught to accept situations the way they are presented to him by maintaining poise. This reverts of idealistic parent-child relationships and how parents are supposed to be understanding of their own children by accepting their children and the most important part helping them grow as people which Jung's father believed he could achieve in his twisted ways.

All in all Jung's parent complex has significantly impacted his relationships. He struggles to form deep connections with others, often using his coping mechanism to control situations. However, through his relationship with Seol, Jung is able to change and become a source of comfort, despite never having been comforted himself.

This character development showcases the power of love and Jung's desire to improve himself for Seol. Despite his upbringing, Jung is able to break free from it enough to form a meaningful connection with someone so special to him like Seol. This growth is a testament to Jung's capacity for change and his willingness to work through his emotional struggles. This also explains why I don't strongly agree with the argument that Jung did not change significantly through the duration of the manhwa when he did indeed but it was conveyed by the author in subtle ways befitting Jung's personality.

This is a silly long theory if you liked it do let me know, I have an analysis on Jung's dad hidden in my drafts.