X-Men and Lawyers

My son (age 6) is seriously into a set of superheroes called X-Men. It seems that one of the characters ("DeathLok") caught his interest the other day and he wanted me to explain if the guy was a good guy or a bad guy.

"Well Son, he's a little of both,” I said. "He's a mercenary."

"What's a mercenary?", he asked.

"That's someone who will fight anyone if someone pays him enough," I answered.

Then my daughter (age 9), trying to put it into perspective for my son, said, "What Dad is saying is he's just like a lawyer."