Although the nickname can be given to ANY girl, it is often applied to girls with the following names:
As they are often the most promiscuous girls in the room.
If you are lucky enough to fall in love with a Chesty McMountains, you are in for a good time. She is fantastic in bed and a terrible flirt in public - although she does have a softer side she will only let you see.
Be prepared for a little bit of a rough time if you are the jealous type, as Chesty McMountains will flirt with EVERYBODY, so if you can't handle that, don't get into a relationship with her.
"How do you not know!? She is Chesty McMountains!"
"You are dating Chesty McMountains!?!?!? Lucky YOU!!!"