Ooh, don’t mind me, I am just trying to be your friend, I definitely never want to have sex with you! I don’t even know what sex is! Is sex a word? I haven’t heard of it before… I know I just said it but… um… wanna hear a joke? Hehe?
You can be just friends with a girl (not engaging in coitus) without putting on this 9 year old boy persona to try and convince her that you are not creepy. If anything, it is way more creepy to put on an act as if you don’t own a pair of genitals and act as if you have no desires and then later reveal to her that the entire time, you fantasised about her every night before you cleaned up and went to bed. Sorry, you shouldn’t put on that persona simply because it isn’t you, it isn’t authentic, people won’t relate to it and they will think it is weird.
The best way to be ‘just friends’ with a girl when you are single (let’s say she has told you she is a asexual) is to do exactly the same as you would with a girl you want to be closer with but just do not make a move. It is simple as that. That means you can still hold eye contact, still be open and honest with her about sexual topics and you can still flirt. Be warned with the flirting though… if you want her to stay comfortable being your friend, your flirting should be not a ‘proposition’ in any way. What I mean by that is that your ‘flirts’ (I don’t know how else to put it) should not come across as a question that she must answer. The question being ‘eh, what about it then? you and me… eh?’. It should not even sound like a question. All you can do is have banter with her and compliment her and still show her you like her. There is nothing wrong with that, just don’t put her on the spot.
If you are not single, then you should not be showing other girls any sign of sexual interest. You should not hold prolonged eye contact and you should not flirt and you certainly should not make a move. It is not fair on your girlfriend. You should treat your female friends exactly how you would treat a guy friend. Try to remove that thought of them having potential in your head. Remove any sort of sense of attraction you have towards them. You wouldn’t like it if your girlfriend behaved suggestively so you should not act like that either.
Back to acting innocent, it should be quite obvious as to why this reduces your boyfriend potentiality. Girls usually do not want to have sex with a 9 year old boy… or a guy that has no clue about sex. If you don’t express anything sexually then she will have no evidence for her imagination that you will be capable of pleasing her in the bedroom. That means she probably would not have even thought about having sex with you… and you are wondering why nothing has happened between you yet. Of course, it would be just a little out of the blue for you to instigate sex with someone who hasn’t even considered you before. Understandably, you have resistance to making this transition and understandably, she will be confused when you attempt to. You know you want to have sex and you know you think about it a lot, so stop caging yourself in…