Stitch Sans rubs an Undertale timeline with his elbow, trying to make it shiny. He can see what's going on inside there, Frisk is shaking that timeline's Sans' hand. Stitch Sans isn't sure whether this Frisk is pacifist or neutral yet.

Stitch Sans fiddles with his belt.

Lately there's been a disturbance on the outer parts of his timeline, just past Horrortale and Undertail. It's obviously not big, but Stitch Sans thinks that he should check it out sometime.

Stitch Sans has seen Error!Sans moving about a bit lately. It's nothing to worry about that much. Whatever that error destroys will be created again sometime. Whatever created that error Sans is obviously out of it's mind.

Stitch Sans put aside his thoughts and waited for the voices in his head.

(JudgementGirl) "I can hear you! I'm sure more people will turn up, too!"

"Good to see that you can hear me." Stitch Sans says, "mighty positive, aren't' cha?"

He shudders as he gets the feeling he gets when a thread has snapped. 

He quickly identifies the source and teleports over. It's one of the newer ones...Freshtale? Underfresh? Someting like that. It's a weird Universe. Stitch Sans replaces the thread.

(TrueSaiyan) "I have a kind of meta question.

How do you know your timeline isn't connected to other timelines just like all those timelines are connected to the main timeline?"

Stitch Sans thinks about that for a moment.

"Well, I'm not entirely sure if my timeline is even a timeline or just a...void thing," he admits, "but this used to be a timeline, so I continue to call it that. But if it's connected to other timelines..."

Stitch Sans looks around the SpaceTime timeline. It's inky black void, it's white crystals that represent the timelines...it's like space. Endless.

"It wouldn't be. A bit like...have you heard of Error!Sans? He has his own timeline thing. It's not connected to other timelines, but he can still travel. It's a bit like that." Stitch Sans explains.

He looks around again. 

"Welp, if you still have questions, I'm open. It's very quiet here."