Swadloon is a round, yellow Pokémon inside of a cloak of leaves. It drapes the leaves over itself and draws them closed around its body, so only a large, crescent slit remains for its face to appear. This leafy cloak keeps the Pokémon warm. Under its cloak are darker green, limp leaves which frame the sides of Swadloon's face and trail down on the sides of its body. The top of the cloak has two semicircular leaves that form a V shape. On its back are the veins of the leaf as well as a bit at the bottom tip of the cloak resembling a rounded tail. Swadloon lives on the forest floor and converts fallen leaves into nourishment, which helps the surrounding plant life grow.
Swadloon, the Leaf-Wrapped Pokémon and the evolved form of Sewaddle. Swadloon's body is covered in leaves which protect it from the cold. In forests where Swadloon live, the trees and grass grow very well.
In The Plan, two Swadloon briefly appeared in a flashback, in the forest where the young N was living.
Swadloon appears to be based on a leaf-rolling insect pupa or prepupa such as a Pamphiliussawfly caterpillar or a lepidopteran prepupa such as a silver-spotted skipper. Many holometabolous insects fold leaves over themselves for camouflage and shelter in their immobile pupal stage, eventually use silk to stick the leaves together and form its chrysalis. It also resembles a walking leaf and the nest of weaver ants. The appearance of Swadloon hiding in its blanket bears some resemblance to the stereotypical portrayal of people suffering from hikikomori (acute social anxiety disorder) syndrome in Japanese media. Its evolution into Leavanny (whose Japanese name is two kana away from "hikikomori") being caused by friendship may also be a lesson.
Swadloon may be a combination of swaddle (to wrap a baby in cloth) and cocoon.
Kurumayu may be a combination of 包まる kurumaru (to be wrapped) and 繭 mayu (cocoon).