What is IM in regards to yahoo. answers.?

This is in regards to a 14 yr old referring to herself as "bi-sexual_lover" -- she'd asked a question a while back in the religion / Christianity section. I was one of several responses / told her that I'm a grandmother with granddaughters her age and was concerned about her 'handle' at her age. To put her time into studying and not be concerned about having a special woman friend at her age. She seemed to have a special situaton that she wanted to talk to Someone about. Offered to be a good listener if that's what she was looking for. After a couple of emails she got more and more rude and obnoxious. I 'called her on it' . Told her what she sounded like. Told her not to respond back unless she cleaned up her attitude and language. Didn't hear from her for a few days and then she popped back into my gmail box. I decided to respond back with Scripture -- after a couple of messages today, she has accused me of stalking her and now is threatening to add me to her contact list so she can Really make trouble for me. I'm not familiar enough with yahoo answers to know what IM even is. I got onto Yahoo. Answers through an apologetics site I'd been on. I like the forum and have answered a lot of questions over the past few months. I've been very concerned about young people and homosexuality. I try to guide them to Friendship and their education rather than getting so engrossed in sexuality, Their hormones are just starting to activate / the best thing to do is learn Friendship. I've only gotten into a few emails with her and a young man a while back. Lots of times I've stated my thoughts and never gotten any response back which has been fine with me. But I'm concerned about this particular 14 yr old and the trouble she may be trying to cause for any one else who tries to help.