lmao he showed me some pictures from a gaming convention he was at once and we were having a laugh at the cosplayers
That's his modus operandi, Bjord, his typical method of seduction. You think you're special, do you? No, Bjord, he shows the pictures to everyone. Do you want to know the science behind it, Bjord? I'll tell you. First, he shows you these pictures as a way of establishing connection, sharing something personal about himself to bond with his victim. This also pressures the subject to answer in kind; this works off of basic principles of reciprocity. You will feel inclined to share something personal in turn, oft-times without even noticing this inbuilt, ancestral sense of reciprocation yourself. Not immediately, you understand, no, that would be too crude - it's a background force, entangling you ever further, ever deeper, in the web that Nessaj spins, making you feel closer, more connected to and with him, without fully realizing yourself why.
Second, we have a very classic abuse of the ingroup/outgroup dichotomy. Putting something down feels like pushing yourself up. It creates a sense of shared superiority, an easy "us" versus "them" setting, another way of bonding with the ingroup while simultaneously raising the perceived status of everyone included in it. It also demonstrates high status from the one doing the ridiculing: to have the gall to do that, the person must be pretty high up the food chain themselves. This doesn't make rational sense in a modern setting, but your monkey brain doesn't live and was never designed for the contemporary challenges it now faces. As if that isn't enough, it additionally signals cynicism. Why is that desirable? Because it seems like a mark of sophistication, of maturity, like you've seen it all and are above these people, a man-of-the-world, like you've seen it all and know better.
We are not blank slates, as some behaviorists once imagined. We are organisms whose more egregious tendencies can be greatly, if arduously, subdued. Nessaj has knows this well, and he has also spent many long hours studying the subtle science of subornation - the fine art of getting you to cross a line without you ever knowing it was there. He teases loose these tendencies that people attempt to subdue. In some cases, this is very easy (see: ingroup/outgroup), in others, it takes more finesse, more skill. Yet, it can still be done, as he has demonstrated.
Cosplayers are a safe target group when it comes to ridicule: certain to bring forth a sense of superiority and scorn in any who see them. This is why they were chosen. You didn't think it was a coincidence, did you, Bjord? The entire scenario has been hand-crafted to allow Nessaj to pull at every hidden puppet-string from which all men hang. And when the strings are seen, they may be seized. Nessaj sees them.
To be ignorant is to be a slave of the world. To be deceived is to be the slave of another man.
Escape his web of seduction and lies while there is still time, while you've still some innocence left -- he will suck your blood dry, he's like a psychic vampire. I tell you all this because I pity you, and because I've seen too many of his victims, too much of his handiwork, to stand idly by while yet another beautiful young man becomes nothing but an empty shell of his former self.
I leave you with this quote, from a man you've quoted yourself:
On the mountains of truth you can never climb in vain: either you will reach a point higher up today, or you will be training your powers so that you will be able to climb higher tomorrow.
- Friedrich Nietzsche
I wish you the best of luck. I've done what I can, the rest is up to you: you have been warned.