" Mack winked. “The sex scenes are also really fucking hot.”
Gavin dropped the book.
Mack and Wilson laughed and high-fived. “I loved that one,” Wilson said. “At least a BB Four.”
“Do I want to know what that means?” Gavin shuddered.
“It’s our rating system for how much sex is in it,” Wilson said.
“But what does BB stand for?”
The whole table spoke at once. “Book Boner. "

― Lyssa Kay Adams , The Bromance Book Club (Bromance Book Club, #1)