2. Sex that's so lousy, it doesn't even count as a full fuck.
3. Sex that's so amazing, or so difficult to score, it counts as several notches on your belt.
Dan: "What do you mean? Where was the rest of her?"
Bob: "It was fractional sex, this chick named Amy. All I had to do was buy her one drink and she was back at my place. She was so easy, it doesn't even count as a full lay."
2. Krista: "How many guys have you been with, Amy?"
Amy: "Two and a quarter?"
Krista: "Two and a quarter? How do you fuck 25% of a guy?"
Amy: "It was this guy name Dan. He was so shitty in bed, it don't even count as a full lay. He had a little dick and he only lasted two minutes."
Krista: "Ah, fractional sex. I've had a few of those. I'm up to 3.4 I think."
Amy: "3.4, huh? Sounds like fictional sex to me. You're forgetting about those two guys you did on Spring Break, and that Jerry guy, and that professor you went down on, and-"
Krista: "Shut up! You made your point."
3. Will: "Well, it took me seven months, $500 in dating expenses, and four bullshit love poems, but I finally got Destiny in bed last night. And man, it was so worth it! She blew my fucking mind! I swear that counts as ten notches on my belt right there."
Steve: "Ah yeah, fractional action, huh? Nice."