Slugpup

Pups are a creature in the Downpour DLC. They are unlocked after completing the Gourmand food quest and achieving one of its endings, upon which they'll begin spawning in shelters on subsequent playthroughs. As they are the infant form of the, they have to rely on the player to survive.

Appearance
Pups look like a smaller version of Slugcats. Pups can come in several different colors ranging from light to dark green with their eyes also ranging in color.

Abilities & Behavior
Pups are initially afraid of the player, running away upon spotting them. The player has to either press the grab button to hold the pups hand or hold the grab button to carry the pup to calm it down. Afterwards, the player must sleep with the pup for its food bar to appear above the players own food bar. The pup will begin following the player who has to throw food at the pup to feed it. Pups can tug on the player and point as well as pick up and throw items like a Spear and jump over terrain. Upon entering a room with a hostile creature like a Lizard, any pups that are not being held will scatter and if one is captured it's food bar will start blinking red, alerting the player so they can save the pup. Pups can also become tired like the Gourmand.

Trivia
Pups were originally Cut Content being shown off in one of the alpha trailers and not appearing in any publicly available build of Rain World until Downpour added them into the game.