Talk:Inaccessible Rooms/@comment-30935099-20170219032903/@comment-32960121-20171022182220

it could be one of four

1- Chara and their creepy smile

2- sans, since he said he will be watching over you

3- Mysteryman/Gaster (he may be able to follow the player as an almost invisible ghost, maybe only seen by "unused" NPCs)

4-Papyrus