Dr. W. D. Gaster

Dr. Gaster is the principal of Hometown's school.

Asgore
Gaster helped Asgore to save his flowers. In the 2021 QnA, he said that Asgore was a good person at his core.

Toriel
Gaster is Toriel's boss. Toriel tends to ramble suggestions for how they could help the children to learn better, which sometimes gets on Gaster's nerves. However, in the 2021 QnA, he said that Toriel was a good person at her core.

Gaster Followers
Gaster is often seen to be exasperated by their antics.

Pre-Story
According to Sheldon, Gaster grew up in the "obscure city of Helvetica", and eventually earned 6 P.H.D.s.

Gaster eventually showed up in Hometown one day, and took over as its principal.

Gaster also helped Asgore to save his flowers, and made protective cases for them to stay in. This resulted in the creation of the SOULFLOWERS.