Daniel_

Well - if you mean a post-op mtf, then I presume (excluding study of a ratio of finger length, which I believe is a relatively robust way if identifying "gestational gender") only a close examination of the genitals or an admission of the situation are the ways someone will "find out". In that case, if someone has already given you the blowjob, it would be churlish to be cross at their revalation - the worst you should do is thank them and not go on another date.

Personally, I take the approach that if it walks like a duck, and quacks like a duck, it's a duck.

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Overhead, the Albatross hangs motionless upon the air,
And deep beneath the rolling waves,
In labyrinths of Coral Caves,
The Echo of a distant time
Comes willowing across the sand;
And everthing is Green and Submarine
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