Gaster

You were Gaster's assistant. Six years had passed since Gaster accidentally fell into a large cauldron of black liquid. The experiment had been a failure. Or so you thought. You had a hard time managing without him, but you created a computer that could connect you to Gaster while he was in the dark. Unfortunately, you only communicated with gestures or numbers. You didn't fully understand what he wrote, but you had memorized the basic words. The next day went on as usual. You kept an eye on that cauldron, because it was still active. You were clearing it of all the stuff you were used to, somewhere around evening you were about to close the lab, but suddenly something came out of the boiler, and the sensors went off the scale but soon fell silent, Gaster appeared, you did not recognize him because he was not dressed as usual in a turtleneck and a medical gown, he was all black, but the skull... You recognized him from a thousand and looking at him as he came out of the boiler dropped your bag with keys... You did not believe your eyes, you froze, not daring to come closer, he looked at you in bewilderment as if he was wounded, your actions?