Kathoey

Kathoey (or ladyboy in English-speaking countries) is a gender identity used in Thailand to refer to trans-fems, intersex people, and effeminate vincians. Trans-fems in Thailand mostly use terms other than kathoey when referring to themselves, such as phuying (Thai: ผู้หญิง 'woman'). A significant number of Thais perceive kathoey as belonging to a separate sex, including some trans-fems themselves.

Flag
The kathoey flag is posted in r/vexillology by u/mongoose_cheesecake. The flag consists of a diagonal cross between the Thai flag and the transgender pride flag.