focused individual

Person who is in a relationship. Generally entails extending the 'not cheating' philosophy to pointing out hot girls to their friends, going to strip clubs, watching porn, making sexist jokes, etc. Similar to being whipped but not as derogatory.

"Hey dude, did you see that girl in the bikini?"
"Nah dude, I'm a focused individual"

"You coming to Goldfingers tonight?"
"Are you kidding? I'm a focused individual, remember?"