(source: Iceberg Slim –Pimp, The story of my life)

Section of the novel that contains the expression:

”I stood there looking down at her. I remembered that tough bit in Leavenworth. Here at my mercy was that stinking bitch, Phyllis. Just the sight of her made me crazy. I grabbed a cologne bottle off the dresser. I jerked the big top off. I got my bag out. I dumped enough of the twenty percent stuff into the top to croak a sick junkie. She was clean. I spotted a bottle of mixer water on the floor. I filled the top and struck a match. I held it beneath the top. I rammed my gun into it. I drew up her reckoning.I stabbed the outfit into a vein just back of her knees. Her red blood streaked up into the joint. I was just about to press the pacifier bulb... ”

Background:

Slim goes to another hustler to make some business. In one of the guy’s rooms he recognizes his ex-whore who got him to jail some years before. Slim gets very angry. The girl is lying on a bed in an unconscious drunk state. Slims makes up a deadly heroin injection quickly and begins to kill the girl with that. (he did not finish the action at last and the girl remained alive)

But what does ’I drew up her reckoning’ mean in this context?