Narumi was the leader of Housen during the 23rd era, the successor of Bitou Makio and the predecessor of Tatsuya Bitou. During the time of the war against Suzuran which killed Bitou, Narumi was in a freshman. Narumi's skill may be on par with Serizawa as he also made Genji had a hard time during their fight. He was shown on par or slightly stronger than Kuma.
Narumi didn't like anyone who use knife in a fight (because of the incident that happened to Makio).