I'm just an over-the-hill Gen-X'er who's not into the latest slang phrases kids are talking these days.
But "a 'pick me' girl", sounds like "gamer girl", or "skater girl", or "camping/hiking girl", or "rocker/goth girl", or "typically male-dominated activity being done by a girl"... all to win the attention of certain male demographics in those circles.
But an extreme example (based off personal experience) of a pick-me girl would be being a total SLUT.
That 7/10 plain jane, girl-next-door type that's trying to win your affections over a 9/10 plastic princess in the same room. And even though princess is allowing you to play the courting game and be in her social circles, Ms.GND is gravitating towards you and needs to think outside the box to gain your attention. And usually that means, playing at being the 'big sister' of your social circle so you're not seen as threat to the princess who's herself is expecting the guy to make all the moves in her direction. Then carry on with your groups activities like going to sneaking into clubs to catch a show, shopping up and down Granville, Lougheed, and Metrotown (when it was peak 90s). Tailgate parties, house parties.
...then before the courting-game is finished between the guy and the princess, and were about to the seal the deal with kiss and the official statement; Ms.GND makes her play behind the princess' back by going above and beyond the 'big sister' role everyone felt comfortable with initially, and pours her heart out in private, alone in a pool house with the guy, with her bikini straps falling off, pretending to be 'drunk', on her knees with her hair tied up for the business... Ace-up-the-sleeve move, to win him over....and it worked! Since the Princess found out that night, and freaked out at both of them, crying betrayal. Ended the courting game and shattered our social circle. But the GND and the guy wound up hooking up and dated for a month.....didn't last long after a pregnancy scare...
FYI, I wasn't the guy, I was another guy in circle who wanted to date the GND, until I found out how easily she was willing to give it up to that guy... Which shocked me since her "big sister" act had us all fooled; I thought I'd be the one to break that rep be with her. Instead I wound up with the Princess, and dated for about a year and half as teenage relationships went. Had lots of fun together. Still facebook friends to this day. It was a hard sell, because I didn't want to be her rebound, second choice, default guy... She just remembered how much fun we all had hanging out, and I think seeing GND do what she did, kind of humbled her in a way of not playing so hard to get.
