Little bones (Remake of Sans's Secret)

(anything in Italics is part of a thought or a dream/nightmare. This story will be in 3rd person limited most of the time, though sometimes it'll be in Sans's Point of view)
Sans never had a childhood, and Dispite seeming like the mature one of the skeleton bros, he's nothing relatively close to mature when he's alone. He's a little. And when thoughts of Papyrus start to turn more romantic than they should be allowed to be, he starts to worry more and more about being rejected as a little. What happens when his nightmares start to get worse?