Hiromi helps create tabletop roleplaying books, with numerous credits, including the best-selling Mage: Gods & Monsters.
| Release | System | Title | Role |
|---|---|---|---|
| 2020 | Scion | Titanomachy | Writer |
| 2020 | Chronicles of Darkness | Dark Eras: Last of the Imperials | Writer |
| 2020 | Mage | Mage Made Easy | Consultant |
| 2020 | Chronicles of Darkness | Dark Eras 2 | Writer |
| 2019 | Capers | Covert | Cultural Consultant |
| 2019 | Mage | Gods & Monsters | Writer |
| 2019 | Mage | Book of the Fallen | Consultant |
| Coming Soon | Mage | Technocracy Reloaded | Writer |
| Coming Soon | Scion | Dragon | Writer |
| Coming Soon | Morra Cinematic Game System | Core | Guest Writer |
| Coming Soon | Mage | Victorian Mage | Writer |
| Coming Soon | Modern AGE | Flight 1701 | Writer |
| Coming Soon | Trinity Continuum | Adventure! | Writer |
| Coming Soon | Eldritch Century | Core | Writer |
| Coming Soon | Mage | Rich Bastard's Guide to Magick | Writer |
| Coming Soon | Mage | Operative's Dossier | Writer |
| Coming Soon | Scarred Lands 5E | Dead Man's Rust | Writer |
| In Development | Fifth Season Roleplay | Core | Writer |
| In Development | Modern AGE | Aetherial | Writer |
| In Development | Modern AGE | Cthulhu Awakens | Writer |
| In Development | Scion | Once & Future | Writer |
| In Development | They Came from Beyond the Grave! | Tales of Depravity! | Developer |