Gaster would lead a new subject to the shared cell of 1-S and 2-P. He placed his hand on the pad outside the room, making the blocking horizontal lazers back away as he led the new subject in.

"What is that?" 1-S asks as he looked at Gaster with glared sockets.

"A new subject." Gaster answers bluntly, pushing you in further.

"They're so small! Smaller than you brother!" 2-P says, looking at you with excitement and interest.

"Yes. They are. And they are incredibly fragile. Just like 1-S, if you hurt them, they will die. Be careful, I don't need to be sweeping up their dust." He says, observing how you may interact with the subjects.