
Literally info from wikipedia "The full presentation of dissociative identity disorder can onset at any age, although symptoms typically begin by ages 5–10." And remember that later he experienced even more trauma that could triggered it and most important is that he traveled trough time to the past because it's a fantasy, so we shouldn't really be so nitpicking about the accuracy of the DID since we don't even know yet if he really have it

Wikipedia is not a super credible source. At its core DID is an extreme form of denial that the trauma occurred because it is too extreme to cope with. Individuals pretend that the abuse happened to an imaginary person. At a certain stage of childhood imaginary people exist for us. The solution to deal with the trauma for children at this stage can be a dissociated identity. Yeah some people may not have received a diagnosis until adulthood; Depending on partial or complete amnesia, similarities between the personalities, and more. But retrospective review of the patient’s history will always show clear DID symptoms being present by the age of 10 with alters generally starting to appear at 6. Adults can also use dissociation as a coping mechanism and that’s its own separate disorder. Most psych literature will never use absolute terms but that doesn’t mean it’s not true tho.

Oh I agree with you it isn’t bad, at least they’re not portraying DID patients as some kind of monster freaks like Split lol. I still love this story, I was just pointing something out really. I hope it didn’t seem like I was trying to deeply criticize the manhwa or the author. My brain just starts automatically shoving information out for psych topics like a computer because I’ve had to think about it so much lol.
As someone who has to know the entire DSM by heart for my career, that’s not how DID works . Baby girl you don’t just develop a personality randomly, it happens due to an unimaginable amount of trauma as a child. Can’t develop it as an adults like ever. And it’s such a complex disorder that doesn’t always cause age regression, disappearance of any personality, or complete amnesia. Idk what that is but it ain’t DID babe.