From Bulbapedia, the community-driven Pokémon encyclopedia.
Satoshi Shirai (Japanese: しらいさとし), born October 5, is a freelance 3D CG illustrator who was first commissioned to provide artwork for the Pokémon Trading Card Game in 2012, with his first images featured on cards from the Boundaries Crossed expansion. Shirai's work for the TCG was his first professional contract after graduating from Kyoto Seika University studying digital creation. While studying his course, he uploaded many of his projects to his personal blog, to deviantART, and to YouTube, showcasing his approach to the creation, design, and animation of numerous original and quirky characters. Several of these characters evolved into subjects portrayed in Lolipop Melancholy, a 3D web comic used in his graduation exhibition. For a complete list of cards that Shirai illustrated, go here.
Shirai's personal site