Glitch: "They came from the real world.  I hacked them here."
Sans: "..............um?"

*Sans clears his throat*

Sans: "Anyways...can we not talk about-"
Papyrus: "CHARA AND I USED TO HAVE FUN TOGETHER!"
Sans: "...riiight."
Gaster: "Chara is...questionable.  They used to seem friendly, but... seeing everything they do now... ... I'm not sure anymore."
Anti: "...n-now that you mention it...they do seem slightly familiar."

There was a knock on the door.  Gaster answered, and a human with a goat monster walks in.  He talks to them for a moment, then leaves.
Gabby is the first to greet the two.
Gabby: "Hello!"
The human jumps.
???: "Howdy, Gabby!"
Human: "... Greetings."
Gabby: "Wait, Prince Asriel?  What are you doing here?  ...who's this?"
Asriel: "This is Chara!  They fell from the surface."

A/N: More mysteries unfolding...