Horror stood within the kitchen of the castle. He was cooking food. A pleasant aroma filled the castle as he did. He cooked as a hobby, as a cope, and to provide the others with what he couldn't have before he was there.
He was the main one to cook for the castle. Sure, Cross and Dust cook sometimes too, but it's mainly him.
He gains joy seeing his friends well fed and happy. Meals are a treasured event in the castle, as everyone sits together like one big family of misfits and they eat a home cooked meal together.
Horror was always excited to learn new skills, make new things, and keep what was basically his family healthy and comfortable. He always made enough for leftovers so that there was no chance of anyone going hungry.
Horror was making sure the food was turning out well, being rather quiet and concentrated as he did.