If you play really bad, girl, I'll give you the Fool's Mate
Chess-Themed Pick Up Lines

Forget about WGM, go and try to get ALEXANDRA BOTEZ (WFM). OMG THAT GIRL IS AS HOT AS A BAKED POTATO.
That's a very simple pick up line
Ayyy girl let's have fun with chess
You know I'll play with your pawns
BronsteinPawn, you ain't kiddin, she deserves a new temperature scale, Suns will get measured as a fraction of her

Dont worry about horrible pickup lines, you are probably not inspired.
Here, take a look at this photo, I think you will find inspiration.

wow.
you guys are really on thin ice.
what about the possibility of just being a polite decent guy and hoping said WFM enjoys the chess game? No??
I didn't think so.

What about being a complete ass h#$@ that does not care about women integrity and hides in the anonimity of the internet to have some fun with his chums?
NOW THAT IS A REAL MAN.

Oh she looks very much like my wife. Wait though, my wife doesn't play chess. She was, however, a member of mensa before she met me. She finds me much more interesting.
Let's see ... think for 15 seconds:
It's a dark knight so ... do you want to move into my castle or do you want my castle to take you?
Dark knight, knight, I see what you did there, hehe.
I'm trying to pick up WGMs online (without any profile picture or personality), so I need excellent pick-up lines. That will be a sure-fire way to succeed.
Here's my solid, well thought-out input:
"Ayyy girl, I'll be ur knight if ur my queen"