According to Anime! Anime!, an OVA for the anime series Bakumatsu Rock
will be bundled in the game Bakumatsu Rock Ultra Soul
. Titled Mystery! Onsen Kaijiken ze yo!!
, it will be about a mystery at a hot spring and will be released on September 25, 2014.
An incident has led to someone's death at Teradaya, which the gang went to for a day trip. A "69" on the victim's leg will be the key to solving the mystery.
Source: Anime! Anime!
, Official site
News submitted by Shadow-Chan
Bakumatsu Rock: Mystery! Onsen Kaijiken ze yo!!