Forgotten friend (nightmare!sans x reader)

(Y/n) a old friend of nightmare and yes i know what your going to say is no nightmare sans never had a friend .Well you would be wrong (Y/n) was one of nightmares only friends the one that would alway come and see him and not his brother dream and don't get me wrong she didn't dislike dream. But she thought that nightmare need more of her time then his brother but one day (y/n) didn't come like she usually did and it continued through the days (y/n) still not showing up. Thats when nightmare mood started to go down hill and the villagers of sun village telling him that he wasn't needed that they would be better with out him this is how he became what he was.

Author note: ok yes i know this is going to be my first reader insert so please don't hate hope you guys enjoy