This is the work of illustrator enakei. Enakei's works are divided into jennie and Enakei, both of which are based on Korean actress Min Hyo-rin.

Enakei is a famous illustrator in Korea. These works are famous for their aestheticism. Their painting style is romantic and euphemistic, sometimes hazy and sad, sometimes bright and cheerful, with clean pictures, soft colors and warm feelings. They are very popular in Korea.

You can search Ennaki's works.