Gaster rests a hand against the glass, staring out into the room beyond along with Frisk. His nails scratch a little against it as his grip tightens for a moment. The question falls like a shove. It's a question he very much wishes he didn't know the answer to. "This is a very delicate procedure. He needs to stay still. But it will also be a very painful procedure, and so he might not be able to." Gaster turns resolutely away, but his anxiety continues to betray itself in the way he twists his fingerbones together. "If he moves or tries to run, things will become...imprecise."

The scientist nods to himself. His mouth draws into a thin, tight line. "Imprecise things are dangerous. So we must make certain that nothing goes wrong. That is our job. Staying still is his."

He leans forward to check the measurements on his side of the console again. They're probably right. He needs to be sure. "I am very glad that you decided to work with us, Frisk. The project made a great deal of headway with your input, in much less time than we could ever have managed alone."