It has been showed that the brain cannot tell the difference between a real experience and one that is vividly imagined... so, yes, you can use your imagination to build up your confidence... and it will even change your self-image...
And, there is no way that it could create mental problems down the road...
Lastly, if I could give you just one little advice on how to succeed with girls... it would be to try to make them feel better about who they are... usually... it never fails...
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