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Firstly...have you seen or met this girl in person or seen her in any sort of "not being able to be fake" sort of way? I know you have her facebook profiles but they're unbelievably easy to fake.

I'm not going down the "oh its an mmo girl, obviously fake" route as my hot friend plays an MMO but better safe then sorry.

Personally I'd get her SPAM off her. If she refuses or makes an excuse start running as its a catfish situation waiting to happen.

Way to get SPAM: "Not really into this whole Facebook chat thing. You got SPAM?"

Also ONLY EVER compliment when they've earn't it and don't ever go down the "You're so beautiful" route. If she does give you your SPAM within the first 5 minutes look at something she's wearing that would have required effort or something. Like her hairstyle or those things they wear in their hair or clothes.

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Fair.
Basically when she does something that makes YOU smile then compliment her. Complimenting women for no reasons DECREASES your chances with her. She'll be getting a thousand (especially on an mmo) a day so be different. Be fun and casual to talk to. She'll be getting a thousand compliments a day but will WANT one from you more and will thus actively seek it out.

Here's a mini guide:

- Are you complimenting her to get something?
- Are you complimenting her to fill space so that there is no silence?
- Are you complimenting her because you don't know what else to say?
- Are you complimenting her so the conversation keeps going?
- Are you complimenting her to make her like you more?

IF THE ANSWER TO ANY OF THE ABOVE IS YES THEN DO NOT COMPLIMENT!!!

Only compliment when she does something to earn it. This can range from making you food, giving you a massage, blahblahblah. The compliment has to feel emotionally engaged to her otherwise it'll go in the "piles of boring compliments i get everyday" pile.
ahhhh it's fairly needy/sappy but it is her birthday. I'd build upon it to be honest. It's hard as I've never done any sort of MMO stuff. In real life I'd send her a text message saying.

"Know your adding another notch to the age today. Felt bad for ya so I sent you a present in the post. Cya later"

then the present in the post would be a "You'll never grow old to me" kind of thing. Then you've emotionally engaged her in two ways. Made her feel upset that you think she's old then made it into another joke and made her feel good.

WOMEN LUV DA EMOTIONAL ROLLARCOASTERZ!