CSO

Complicated Significant Other, for example being friends with someone who rejected you but he's still kinda flirty, etc. There's no other name for your relationship. Can only be used when you're single and he's your or one of your closest things to boyfriend, lover, etc.

"Are you two dating?"
*leans in and whispers*
"he's my CSO I was talking about!"
"Oh!"

by cupcakes3659 December 12, 2016