The Porgs weren’t technically a character in the Sequel Trilogy but more of a species. There was one that did hang around Chewie and stow away on the Falcon, and kind of became a sidekick, so I went ahead and included them on this list.
There is no denying the cuteness of this hairy little puffin like creatures. Rey encounters them in The Last Jedi when she travels to Anch-To to find Luke Skywalker. They are curious little creatures who provide laughs without being annoying or unbelievable like other species in the saga.
As mentioned before the best part about the Porgs is their interaction with Chewie. At one point in The Last Jedi, he’s about to roast one for dinner. Suddenly a live Porg shows up and gives him puppy dog eyes, and Chewbacca decides to forego his supper. Having to deal with the Porgs likely helped the Wookiee overcome some of his grief at losing his best friend Han Solo, so they did also serve a positive purpose in the film if it was intended or not.