Let’s make an Undertale AU with characters from different Universes! Day 4 Underestimated (Sans)

Today we need a character to replace Sans’ role as the underestimated character. You can choose a character from any TV show, Video game etc as long as they follow the rules.

Rules:

1) no voting to replace a character with a character 2) no repeats that are already on the board 3) keep it appropriate

At the end of the day, the reply with the most upvotes will be chosen.