The "allure" or charm of m2f transitioning is both psychological and physical. The pull is felt because of an inner urge or predisposition.

(1) It's psychological because there are pre-existing (inborn) feminine personality traits the extent of which varies depending on the individual. The more inwardly transgendered the greater the tendancy to naturally express this aspect of ones personality.

When the itch to do so intensifies and the time & setting are permitting, an m2f transgendered individual can relax and allow his feminine personality to fully manifest and self-express. If this pre-existing feminine self is deeply ingrained or has evolved and strengthened over time there can occur a total or near total conversion in gender identification. One undergoes a powerful, fundamental psychological transition from male to female as the female personality takes over, influencing all aspects of behavior, thinking, feeling, likes & dislikes, attitudes, opinions & preferences all of which are markedly different (even contrary to) the normally dominant male personality.

The maleness of ones normal personality is greatly diminished. It fades in importance and influence. One is now barely aware of that 'normal' everyday self or altogether forgets it. 'He' becomes 'She' in a very genuine sense. Totally immersed in his normally repressed inner female self, one that is independent and as real as (or even more real than) the coexisting male personality, the m2f individual looks, acts, thinks & feels in a manner that is predominantly if not wholly feminine. And does so in a way that is legitimate, authentic and true to inner herself.

(2) It's naturally arousing to transform to your own ideal 'girlfriend'. When you look in the mirror the (subdued) male in you doesn't recognize the sexy, sultry, alluring girl reflecting back. This is at once confusing & arousing, empowering the female you see in you, now freely expressing in everyway possible. As she exerts more influence you fall for her allure & are liable to do things you normally wouldn't. Once overcome with and immersed in feminine feelings, sex is intense & overwhelming.