The only way to confirm a ladyboy is check her "pussy". If you see scars on both sides, than is a ladyboy. "無水就一定係LADYBOY了", I don't think so! Some girls if they don't have feel, no water!
just find that ching totally cannot prove she is ladyboy
if she is a real woman but you said she is ladyboy
you totally hurt that girl
may be you think you are very smart yourself