Being needy with someone you are not romantically involved with. Using phrases such as 'why haven't you called back', 'I left a message, did you get it', and the ever so famous 'Did I do something wrong' when the person is just flat out too busy to get back to you.
I sent you an email yesterday and called today, did you not get them? I need to talk to you, are you busy? Are you mad at me? I am starting to develop Needy Girlfriend Syndrome over here!