shadow skank
A very promiscuous girl who is unnoticed because of her sluttier friend who casts a shadow over her through her skankish acts thus not appearing like a slut even though she really is
"Did you know that Jess had sex with four guys last week?"-Guy 1 "No way man, her best friend Celeste sleeps with tons of guys every night so I had no idea! What a shadow skank!!!!" Guy 2