Alphys didn't know what to do now. She knew that Sans would be upset if he saw his father, so...

"U-uh... Gaster? Can you stay down here?" She asked.

Gaster didn't say anything, and just nodded. Alphys smiled. She really hoped this would work.

Alphys went up the elevator. She went to Snowdin (via boat).

"Sans? I want to show you something." She admitted.

Sans was confused, "What is it, Alphys?"

"Um... you might not like it..." She sighed, "Just... follow me."

She went back to the boat and they rowed to Hotland.

They went in the elevator and once they got down, Sans was surprised.

"Oh. It's YOU." Sans grumbled, angrily.

Gaster was surprised, "I'm sorry..."

Sans didn't listen to his words and left without saying anything.