LJBF, is used by women, in an honest sense. She doesn't ****ing find you hot, and than say let's just be friends to **** up your game and make you chase her... well some do, they're fun, so why am I even saying that? Oh yeah, you have to use it properly!
It's contextual, So I can't tell you now whats going to happen next... without any knowledge, and you given no passion to your argument, I cannot reveal to you anything.
I can say that if she wasn't EVER feeling anything, and you LJBF'd her than she won't come back. She thought that you were a loser, just somebody trying to win at a game that you had no chance at in the first place, than you got angry and said let's just be friends... I would be relieved I didn't have to break it to you myself if I was that girl.
If you were teasing her, and she was laughing, and she made a wrong comment, THAN you LJBF'd her, she will come running, and probably bring a few friends.... It shows your not to be ****ed around with, and she will be smarter in the future.
So if you really want to know what to expect the next time you see her, expect a friend, that is the bottom truth in the line. If it was obviously a lie in her mind, it depends on what kind of girl she is. If she wanted to get to know you, and you LJBF'd her to protect yourself, than you can rightly expect her to still like you.
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You have to remember though, you didn't tell me anything, so read what I say and answer accordingly... Ask the right question... That's one of the stickies up there, one line topic, and one line questions are boring, and they show you really don't care about the outcome, you also won't get too many open responses.