Tommy Monaghan's first appearance, and the first comic in the Hitman: A Rage in Arkham trade my lone issue of Batman Chronicles came from.
Monaghan had the misfortune to be created in the Bloodlines event, which Steve Dillon describes in the introduction to this trade as a crossover designed to create a swarm of heroes and villains to run up the flagpole, and see who got saluted. Most of the characters were lucky if they could get a one-finger salute.
The conceit, as I understand it, was aliens (like the large fellow up there) showed up wanting to feast on human spinal fluid. And sometimes when they did this, the person got superpowers. Glonth there feasted on a mob boss, Bob Dublez, Tommy was supposed to kill, then took a bite out of Tommy. Tommy got x-ray vision and telepathy out of it, plus a bounty on his head from the mob boss' conjoined twin sons.
I mean, he didn't even kill the guy, and a bullet to the head probably would have been better than a giant alien bending you over a table and jamming a Xenomorph-like extendable inner mouth into your spine.
Jason Blood, as you can imagine, wants no part of this bullshit, but too bad. Glonth showed up at a wine tasting Jason attended, and he and Etrigan are soon sword-fighting in the street, using police cars for swords. Etrigan shows a measure of precognition I didn't know he had, hinting to Blood about Hitman's role before Tommy's even been bitten.
Jason attends the funeral for the boss, knowing there'll be trouble. Etrigan just wants a fight, and some chaos. Glonth shows up, declaring Dublez had the best tasting spinal fluid ever, and he wants to see if the sons, with a super-sized conjoined spine, will taste even better. I am completely serious about that. Tommy shows up planning to kill Moe and Joe Dublez and get the price off his head.
Visually, McCrea pretty much has Tommy's design set from the word go. He does rock a red scarf or neckerchief during all his appearances in The Demon, I assume for a splash of color. That's gone by the time he shows up on Batman Chronicles and his own ongoing, but everything else is there. Sean Noonan is pretty much set, although Pat looks much more like a strung out junkie here.
In terms of Hitman's personality, there's farther to go. Tommy's smartass tendencies don't really appear until he shows up in Etrigan's ongoing, and his whole code about not killing "good" people isn't apparent. Not that there's anyone in this comic he would feel qualified.