After graduating at a high school in Nakano, he began working as a manga artist in Tokyo.
[1] In October 2005, Miyajima received the Magazine Grand Prix Encouragement Award for his work Sakka no Tensai (サッカの天才).
[4] Miyajima started in Weekly Shōnen Magazine by illustrating the short-term series Suzuki no Shiten in 2009.
The following year, he illustrated the series AKB49: Ren'ai Kinshi Jōrei, which is based on the Japanese idol group AKB48.
[11] He also wrote the original story for its manga adaptation, 22/7 +α, which was serialized in Sunday Webry.