There are quite a few different interesting characters in the Undertale game that players will remember due to their unique personalities. Also, throughout the plot, their character is revealed more and more, allowing you to find out more and more interesting details of their history, as well as some facts about them.
One of the rather comical characters in the game is the younger brother of Sans. It’s a skeleton in red named Papyrus. A very kind character by nature, who is a key figure if the player wants to get the Pacifist ending.
He has a dream to become one of the Royal Guards. That is why he chose Undyne, who is the head of the Guard, as his mentor, who trains him. In general, they have a pretty good relationship and are actually friends.
In Undertale, his older brother is shown as a joker who always teases everyone and everything, but when it comes to the skeleton in red, Sans behaves extremely caring towards him.
Another rather interesting character in the game is Mettaton, who was invented by a scientist named Alphys. He hosts many entertainment programs for the monsters living in the Underground. That is why many monsters love him very much, as he is a rather popular person who brings them joy with his funny shows.
He is very charismatic and self-confident. He can first be seen in person in the laboratory when he breaks down a wall. After which the main protagonist gets on his show. Prior to that, it is used by the skeleton in red as a puzzle machine when the player is in Snowdin.
He also has his own ending, in which he can become the ruler of the Underground if the other two potential queens Undyne and Toriel are killed. It is also mentioned that the skeleton in red will work with the robot.
So if the player is a fan of pretty cool and funny characters, then he will definitely like Papyrus x Mettaton. Therefore, this is an additional motivation not to follow the path of Genocide and not kill them, so that there is still an opportunity in the game to meet them.