This is not a TAAT but that is about a horrible violent attack and this question is quite separate.
In any sexual encounter, do you have the right to expect the other person to disclose their biological sex if they visually appear to be of the other sex?
Essentially, does a lesbian have the right to be upset if the person they were female before they got naked has a penis?
Does a gay man have the right to know that someone who appears to be male has a vagina before he has sex?
Does the nature of the encounter matter? If it's a casual encounter, is the onus on the person who appears to be the other sex to come clean in advance, or is it the responsibility of the other person to check before proceeding?