He produced Sonic 2006. The wiki says he left in 2005, but Sonic 2006 came out the following year, so that can't be right, can it? I would assume he left in 2007 if a game released in 2006 was the last project he worked on at the company.
06, to my recollection, started development sometime in 2004 which would have left plenty of time for him to work on the game as a producer, before leaving in 2005.
Yuji Naka was originally the game's executive producer before leaving Sega in March 2006, but he's not anywhere in the production credits when the game came out in November. So if Masahiro Kumono left in 2005, it seems unlikely he'd be credited since he would have left before Naka, who wasn't credited. And the game was obviously nowhere near completion at the end of the 2005, too; a lot of concepts and ideas still needed to be finalized. Considering Kumono was still doing various interviews to promote the game late into the year, I'm pretty sure he was still at Sega in 2006: https://sonic.sega.jp/SonicChannelOld/creators/008/index.html https://web.archive.org/web/20081007205442/http://sega.jp/segavoice/vol59/
