"FTM" stands for Female-to-Male, and "Transguy" refers to a transgender man. In the context of porn video tags, "ftm-transguy" indicates content featuring a transgender man with a feminine assigned birth sex who is transitioning or has transitioned to male. This tag is used to help viewers find videos that cater to their specific interests and preferences. Remember, this term may not be in English, as you mentioned, but it still carries the same meaning