Slakoth is a brown, quadrupedal Pokémon with sloth-like qualities. It has coarse, shaggy fur with two dark brown stripes on its back. There is a scruff of fur on top of its head, and it has a large, pig-like pink nose, pink eyelids, and dark rings around its eyes. It has long, lanky arms, but shorter legs. Each paw has two sharp claws, and there are pink paw pads on the back feet. Its underbelly and read are also pink.
Slakoth lolls around and sleeps for more than twenty hours a day, which can make those around it drowsy. Since it does not move very much, it does not need much food and only eats three leaves each day. Its heart only beats once a minute. It is capable of regaining lost energy through the use of its former signature move, Slack Off. It makes its nest in tropical forests, and keeps the same one during its entire life. However, it can travel far by swimming in rivers.
As its name implies, Slakoth appears to have been based on sloths, specifically two-toed sloths. It also has some similarities to human infants, such as spending more time sleeping than awake, and primarily lying on its stomach, as babies do not have the muscle mass to hold themselves upright.
Slakoth may be a combination of slack (to be lazy) and sloth as well as a play on the phrase "to slack off."
Namakero may be a combination of 樹懶 namakemono (sloth) and 怠ける namakeru (slack off/laze around).