Previously a member of the Omi Alliance, family unknown, he was among the many men who had fought the Murasaki Family between 2012 to 2015, before Murasaki's disappearance.

After he was inevitably gapped into Gensokyo long after Murasaki, he was determined to regain his own power as a yakuza by any means necessary. He attempted to stage a coup during a normal work day at Murasaki Construction... to laughably predictable results. Shigomi eventually just sued for peace with Murasaki.

His name is a mashup of Shigaki and -gomi, the Japanese word for "trash", as a reference to his real world counterpart, Trash-chan.