However, TRPV1 receptors are all over your body, because any body part might bump the hot stove. Like with any amount of heat the body detects, your body attempts to cool down when you eat spicy food. That's why you have reactions like sweating that are more frequently triggered by a hot summer day or bustling kitchen.
As you might have guessed at this point, there are TRPV1 receptors in your anus.
When you eat, say, a habanero, the capsaicin isn't completely digested. As it passes through your digestive tract, it triggers TRPV1 receptors, which is why some people experience cramps or an upset stomach after eating something particularly spicy. By the time the digested food reaches your anus, there's still capsaicin in the food waste and your butt feels the burn.