His works include the original scores for Bean Cake, Ocha Cups for Christmas, One, Afrika, and Soul Sacrifice.

In 2008, Hokoyama composed, orchestrated, and conducted all the music for the video game Afrika.

"[2] In 2009, Hokoyama provided a few orchestral cues for cutscenes in Resident Evil 5.

[3] Following that, Hokoyama then co-composed, orchestrated, and conducted the music for the 2013 PlayStation Vita game, Soul Sacrifice.

He would later rejoin Mitsuda to help compose new music for the sequel, Soul Sacrifice Delta.