Inside Papyrus and Sans's House. Sans was drinking his bottle of mustard as he sat on the old couch lazily. “Still better than ketchup I always say” He remarked playfully. Sans was a skeleton with sharp teeth, with one being gold. his red eye shows to reflect how “corrupt” (mainly emotionally hopeless) he’s gotten, so when it flickers, it would be yellow and orange. He holds in a lot of emotional stress, so he’s constantly radiating his powers and eye 24/7, which mostly affects his jacket fur.