Board Thread:General Discussion/@comment-25324366-20160802162300/@comment-4383275-20160827052109

I don't know about So Sorry, but I'd certainly wager that Sans knows Glyde and the Annoying Dog. After all, the Annoying Dog was in his and Papyrus' house, and the Mysterious Door houses it as well as Glyde (exclusively, on the outside of the door).

More importantly, Sans seemed to be heading towards the door in Snowdin, and asks Frisk "hey, are you following me?" when approached. Glyde also seems to have meta-game knowledge like Sans, as he uniquely aware of the existence of his own stats and refuses to give them to the player.