[Patrick]

I hate when girls do this..
So she wants to be with you but not tell anyone?

Tell her to go ****.

Seriously though, Its wrong for alot of reasons.

Shes probley seeing someone else.
Shes ashamed of you.
Shes a prostitute and is afraid incase someone tells you if they see you with her.
She might also not like you but doesnt want to hurt your feelings by turning you down.