this is a level of physical fitness that is just above cheerleader buff (which is just skinny with a nice rack) and butch buff (looks like you could play JV football). girl buff is like "i know my way around the gym, but my legs arent to jacked to wear pumps and a dress".
girl buff chicks can usually carry themselves well and wont fall for run of the mill shenanigans, you need advanced, more tactical shenanigans or she will literally sock you in the face. oh, and that belly you put on over winter, she wont say it, but she sees it. work on it.
guy one: i dont know about you guys, i love a girl that works out.
guy two: like butch buff chicks?
guy one: hell no, like girl buff. ill beat the brakes off of a girl buff chick. they are like cheerleaders with abs and ripped up muscles.
guy two: yeah, we need to get on that action.