I would like to expand Doomd's answer.
As they said, the combination 7-2 is the worst possible hand in poker.
However, the interpretation of this is not vague but actually very precise, supported by another thing the character said in the movie:
"[...] I was the last person people would want to see in front of their door."
As well as the fact that in his profession he seemed to mostly work completely alone.
You can see clearly that the cards are facing away from the character in the tattoo (as in, how one would hold their cards in their hand), it is not the wearer who is holding the cards. Instead the wearer is showing the opposite their own cards (which is why the position of the wrist makes sense here).
So the interpretation of it is, imo, that if you see this tattoo you see a 7-2 in your hands, meaning that by meeting this person you just got dealt the worst possible hand by them. You are best off never meeting them.