What's this? / ULTRA-SOULS
| Composed by | BACHI BLUE |
| Arranged by | BACHI BLUE / Shogo Ohnishi |
| Published by | MarvelousAQL |
| Catalog number | GNCA-7210 |
| Release type | Game Soundtrack - Official Release |
| Format | 1 CD - 4 tracks |
| Release date | April 23, 2014 |
| Duration | 00:17:24 |
| Genres |
| 1 | What's this? | 04:18 | |
| 2 | What's this? (坂本龍馬ver.) | 04:25 | |
| 3 | What's this? (instrumental) | 04:18 | |
| 4 | What's this? (坂本龍馬ver.) (instrumental) | 04:23 |
