He is a skeleton with sharp teeth, with one being gold. Sans's red eye shows to reflect how “corrupt” (mainly emotionally hopeless) he’s gotten, so when it flickers, it would be yellow and orange. Sans holds in a lot of emotional stress, so he’s constantly radiating his powers and eye 24/7, which mostly affects his jacket fur. He wears a black winter jacket with a jacket fur flame hood and a gray cotton hoodie, and a red sweater with a golden chain with black pants that have gold strips.