"TS" stands for "Transsexual", and "Feet" is a reference to foot fetish. So, the term "ts-feet" refers to a porn video involving transsexual individuals engaging in activities that cater to a foot fetish audience, which could include licking, sucking, or worshipping feet, among other related acts. This tag signifies that this is a video specifically for those who have an interest in both transsexual content and foot fetishes