As of August 9th, bassist BB is no longer a member of FUTURISM・BOYZ. His departure is sudden and was unexpected, even to the other members of the band―it seems that he just suddenly decided to quit music, for reasons unclear.

For now, the other members have decided to continue. For their scheduled live on August 14th, they will appear as a three-person unit. For the session live which BB was scheduled to appear at on August 17th, guitarist YUKIHIRO will take his place.

It's very sad, considering that those four people have been together since forming Arc. The members say that there's still a spot for BB if he decides to return.

-- [Update] Guitarist YUKIHIRO just posted about the situation in his blog:

Apparently, BB had first mentioned wanting to leave the band in July. He and the other F・BOYZ members had several meetings about it with KISAKI, and through those talks, BB decided not to leave. ―Until August 9th, when he suddenly announced that he was leaving, with no further discussion.

(This is unrelated, but I found it interesting: it seems that FUTURISM・BOYZ was originally intended to be a five-member band. At the last minute, the fifth member changed his mind, and so the band was left with the exact same lineup as Arc. Now that BB is leaving, it seems that FUTURISM・BOYZ will be a three-member band... quite a change from the beginning intentions!)