Not really. At least depending on background Edwin's issue in the past was excessive anger and the ways he'd give in to it, not lack of emotions. His mother taught him to control his emotions and to lie to people he despised about his feelings towards them (which i guess is the base for social chameleon or butterfly traits)
(Caveat before replying: I am not a trained psychoanalyst, but am somewhat familiar w/the field, and had major social disassociative tendencies myself, growing up; seeing people as behavioral patterns of varying predictabilities, rather than people, tho that bothered me as I could feel it was wrong. It was only in my 20s that this began to self-correct, after seeing strong counterexamples to my mode in certain other people)
Sociopaths do NOT lack emotions. They simply lack empathy and conscience, like psychopaths, but psychopaths are BORN that way, and DO tend to have (oft chillingly) muted emotions, while sociopaths BECOME that way from negative experiences, and tend to have difficulty regulating emotions. Sociopaths can apparently have a limited empathy that manifests more as a focus on loyalty to family and a small circle of friends, but lack real empathy or conscience.
Now..
MC is emotionally detatched and definitely has flat affect, but has a strong concern, as the story begins, as to whether or not he is a good person. People with no conscience or empathy do NOT ask themselves that question. EVER. It would never occur to them to even think about it, much less care.
MC has issues, and possibly some sociopathic tendencies, but an actual sociopath or psychopath would NOT have thought to advise The Carnations to have each others' backs; that sort of social/emotional awareness would just not have been there in such personalities; antisocial types are blind to such things.
A sociopath MIGHT feel appreciation for his mother doing porn to support him, but likely would not have maintained a real concern over reciprocating affection, if such regularly inconvenienced him; at some point, anger, impatience, etc, would have derailed the relationship into more negative habits.
My two cents. Not a shrink, but am fairly familiar w/the subject.
EDIT: In rare cases, a psychopath raised in a VERY loving home can have a sort of reverse effect to sociopathy, becoming more socially attuned and integrated. The one example I know of (a doctor who realized he was a psychopath, from his brain scans), nonetheless exhibited excessive competitiveness (w/n willingly lose games to his grandkids to spare their feelings), unwillingness to share food (IIRC), etc. MC is not overly competitive, shares food, and (importantly) thinks in terms of high ideals, not just material wants, whereas psychopathic speech patterns are natively almost exclusively materialist unless prodded into other spheres by outside sources
