When I was conscripted one of my subordinates in army was probably a psychopath, he would always have problems with obeying rules and so on and constantly was hard to deal with. He was very hard to read because at times he would act very sissy-like, like he had this tic-movement that caused his jaw to tremble like he was about to cry and generally looked like a babby, was among the shittiest of all privates, constantly wearing stuff in wrong way and doing everything wrong, but at other times it was clear he was capable of doing things correctly if he only wanted, and then suddenly he might get mad about something like not being able to find something which made him punch a wall so hard his knuckles started to bleed. Scary stuff. Sometimes if you would talk to him he wouldn't look you in the eyes and at other times he had this sinister, piercing look. Very erratic guy all in all.
At some point he started having panic attacks, i.e. like if we had to go out fast and put on battle equipment he would literally spend 15 minutes trying to get socks on and then started crying and shouting like a baby, or if we got already outside he would just collapse in to the ground crying and just stay there catatonically and complain about how he was too tired to continue. Just these confusing melt-downs that were hard to watch since we kinda knew he was just playing but you had to take it seriously (there could be big uproar if you just told a rookie to man up and stop acting since there were people with real problems, but with him it was p obvious it was all pretense). You wouldn't know if it was more pathetic or disgusting. When we went to the shooting range we were always afraidly joking if he would shoot himself or others.
He was deemed unfit for service maybe after a month (we obviously told about him to higher officers) and when he got the releasing papers he was suddenly normal and jovial again. I remember changing some of my stuff with him (they got some never gear than us and it doesn't make a difference what you return to the material center after you leave), and in the exchange it was clear to me and him that he was just playing earlier, like you know we smirked in that way like yeah we know, non-verbal communication. Weeks later one of our mates met him at a bar during holiday and he bragged about how he was merely pretending to be retarded to get out from there.
He came out more as pathetic, extremely unbalanced guy even though he reminded typical Patrick Bateman in many ways, he was pretty good looking, had won some competition in mathematics and was among the best chin-up pullers in Finland winning some national competitions, so there certainly was no problems with his health nor was he too stupid to wear things correctly, so it was clear he was doing it on purpose. Also during the visitor day his family visited and he had like 13-year-old girlfriend and apparently saw nothing wrong or weird in that.
No one particularly liked him and he went really far with his act, pretty disgusting person in general now that I think about it. It was like he had no shame or pride but still is pretty successful in life, he seems to be in banking and insurance currently now that I googled him lel.
I don't think any of us considered him to be a psychopath at the time, and even for me it clicked couple years later, that he fits most of the characteristics. The thing is he didn't come out as cool and collected what you think of some movie archetype but was rather explosive and just bewildering with the lenghts that he went with his act, like how can anyone live with himself after doing that kind of shit, like he had the target of getting out and was ready to manipulate the shit out of everything to reach that goal and didn't give a flying shit about what others thought of him. Seriously if he had shat his pants one day none of us would've been surprised. And also like what you can do with a person like that? When one has no shame or remorse. Kind of like if you tried to engage you couldn't win since he doesn't learn from punishments and even lacks the means to truly understand any moral values. You would only end up stressing yourself etc. I guess they really are a different species.