There's not a lot of info online for this artist but I did find this small bit of biographical information on the Square Haven website.
"Jun Suemi is a manga illustrator. His early work in videogame illustration included monster design for Sir-Tech's Wizardy titles. He has done character illustrations for such videogames as Front Mission 2. More recently, he contributed card illustrations to Culdacept Saga."
See more of his paintings in this gallery. Jun illustrated a series of cards most of which are inspired by monsters, click the links near the bottom of this page to see examples.