I'm a loaf of bread

In Jujutsu Kaisen, Mahito states that he alone is able to see and perceive the soul. The soul  is like any other organ, apart from the fact that we are unable to see it.

As an organ, the role of the soul is to transfigure in response to external stimuli. These transfigurations give rise to our emotions, which we experience as feelings. Our body then responds to these feelings in a multitude of ways, and these responses can be voluntary, involuntary, or controlled by us to some extent.

Humans are a social species. We crave connection, however, that same connection also changes us. By interacting with someone, even for a passing moment, they still elicit responses from us.  By simply existing in society, we react accordingly, pushing ourselves to fit in and behave appropriately.

This is the thing about humans: We alter our own self-expression in order to continue existing in the circles and spaces that we live in. Inevitably, we transfigure the souls of ourselves and each other on a regular basis, whether we like it or want to or not. The changes that we experience internally from these interactions can and do manifest themselves outwards in physical, tangible forms.

Choosing not to wear something we want to, for fear that we will stand out in a bad way. Ordering a meal we otherwise would not have and trying something different, because of a friend’s recommendation.  Choosing our words differently, depending on the circles we’re currently with. And, sometimes, even changing our own behaviours, due to existing next to someone we respect.

Satoru, despite having a preference for Cola (which he orders when he’s alone), orders the same drink as Suguru whenever they’re together.

Due to the social pressures of fitting in, Miwa’s mother dyes her blue hair in order to have her fit in with the rest of her classmates.

Ijichi is fearful over his performance, and sincerely wants to protect Itadori, because of his respect for Nanami, whom he doesn’t want to disappoint. 

In the anime, Mai is depicted as dressing and behaving much more effeminately, due to family pressures, expectations, and oppression regarding her womanhood.

Our relationships and interactions with people do lead to changes in our souls. The longer a relationship lasts, the more permanent these changes may end up becoming. These changes are often not just internal; they even manifest in our physical exterior and in the ways in which we outwardly express ourselves.

Nobara, by most measures, was tomboyish as a child. Beating up boys on school grounds, running away from teachers, even kicking her own schoolbag across the yard, and playing video games with her friend’s father - fighting games, no less.

However, after meeting Saori, her demeanor changed. From someone who beat up bullies in school and did victory dances over their bodies, she started becoming someone who started to speak with a gentler tone of voice, and tried to act in a way that was more refined and dignified. Because Saori was someone whom she looked up to, as someone who was an outsider to the town that she hated living in, Nobara wanted to mould herself to become more like the person she respected. 

Her fascination and idolization of the city still followed her for years, even after she lost Saori. 

On a bonus note, it’s sad to see in Shibuya, how Saori reminisces over Fumi and Nobara. Saori knew that Nobara idolized her, and therefore was afraid to keep in contact with her after she left. She feared not being able to live up to the person that younger Nobara imagined her to be. However, from Fumi's reflections, and Saori’s ruminations, we can see how external these changes were for Nobara, that those around her noticed them so clearly.

Touch is also an important part of social connection. There is much research on humans and primates regarding the importance of touch in conveying emotions, with an acknowledgement on how such communication and expression of emotion via touch is fundamental to human development, communication, and even survival. 

Touch can lead to multiple emotional responses within us, such as calmness, relief, contentedness, or even fear and discomfort, depending on the touch. These emotions are due to the release of chemicals within the body in response to said touch, such as the release of endorphins, oxytocin, and even adrenaline. 

In other words - when we touch someone, we potentially alter them biologically, even if said effects are mostly temporary.

Humans also have the ability to transfigure our own souls. This take may be slightly farfetched, but in Mahito's eyes, someone who is aware of the outline of their own soul might very well be just someone who is aware of themselves - their ego, their self, and where their feelings arise from - someone who is, to some extent, able to control their emotions. 

In a way, self-awareness and the ability to control one's emotions is a form of power, and this is the power Mahito exhibits when using his abilities to his advantage. We can exhibit such power in much more simpler, metaphorical forms, such as slowly becoming the person we wish to be by following in the footsteps of those we respect and admire.

In short, it would be exceedingly shallow to reduce the curse of humanity as an allegory for SA. 

Our curse is something much deeper, more sinister, interwoven into the very threads of our design and being. It is that the very thing we need to survive and hence desire, yet, it is the same thing that can also destroy, warp, and irreversibly change us: Connection, and the indelible marks it leaves upon us.