Your average punk, Rummy seems distinctly anti-social unless you can do something for him. The young man has an intimidating streak and something about him tells you he shouldn't be trusted farther than he can be thrown.
Not much is known about Rummy, but he has been observed stating he's lived a life about as filled with crime as his current time in Limbo. On top of that, he seems to know his way around a baseball bat.
Rum has kept to himself as a loner, instead being found running back and forth running errands and participating in nearly any illegal activity that'll pay. He doesn't seem very good at interacting with people, and aside from a few brief conversations and a couple more extensive talks relating to purchases he hasn't actually met anyone.
His vice may be wrath but he also possesses a greedy streak, actively vying to get house Malphas as high up as possible despite being the only person actually there. You can probably assume he would do anything for a couple of ar!up's, or some cold hard cash.
So far, Rummy has only interacted with others a few times: during the purchase of his iron bat from Xander and when he chased Sena, Bane, and Johnny out of South-Gate because he didn't want them starting trouble in Malphas territory.