Looking back at the origin of laughing jack is interesting because it makes me think.
Isaac would definitely be charming. He was able to get a blind lady to his home for tea, there had to have been some level of trust there, since she was older and blind-- which means she's an easier target. Probably called him a "nice young man" which makes me wish Isaac didn't turn out the way he did. Maybe she could have even become his mother figure. But then again, I just realized that she could've been the owner of the cat, which might've been one of the reasons he targeted her.
He mainly targets those who cannot fight back. Who are weaker than him and he can easily over power. (I don't know if I could say the woman is an example of this since he didn't necessarily target her.) I suppose this could mean he craves control, and gets that from targeting those he views as weaker or less than.
There's a possibility he targeted the boy because he saw himself in him. While he is a man with a heart full of rage, do remember he is still a victim of abuse as well. He did carve "unless worm" into the boy , which is what his mom used to call him.
Okay this one is just because I'm pissed off at people. But isaac is NOT a pedophile, which means LJ IS NOT A FUCKING PEDOPHILE. Trust me, I'm fucking sure it would have been written into the story if he was. He shows no romantic or sexual interest in children. If anything, he shows a level of disgust towards children. Calling them ugly and using them as a punching bag. Whenever people say LJ is a pedophile, it makes me wanna strangle them (that's an over exaggeration, I don't actually wanna strangle someone). Just because of how fucking disgusting that is. LJ is a monster, but he's not THAT kind of monster. His creator is a pedo- but he is not.
LJ's intelligence doesn't match up with Isaac's. He doesn't know what sex or murder is, not even kissing. As seen when he was in the box.
There is a possibility LJ is obsessive and/or possessive with people he's close to-- maybe out of fear of them leaving or getting hurt/taken away.
LJ and Isaac are not necessarily the same, they're very similar, but have enough differences to classify them as different people. Though LJ and Isaac still share probably about 100-74% of interests.
LJ and Isaac are fruity /hj
Literally everyone in the origin of Laughing Jack needs therapy
Isaac's mom took her anger out on Isaac- possibly because he was an easy target for her. She was a victim of abuse as well.
Isaac's father possibly never loved- or fell out of love with his "beloved" wife.
Isaac has difficulties in processing love/affection and doesn't know how to express his feelings properly (this is just a personal headcanon)
There's a very high possibility that LJ was quite literally the only thing that made him truly happy.
LJ is most likely as mentally mature as Isaac, so that they'd age and mature together. Much like a childhood best friend, perhaps.
Isaac is seven years older than LJ
LJ was meant to be what Isaac likes, I'm assuming. So he could have just been a tall , rainbow clown because that's what Isaac was interested in.
Isaac probably has anger issues,
Remember that I'm not a professional, nor am I the creator of these characters, so I'm definitely wrong with a lot of things
Sorry for the long ask
Mans just dissected the whole story-