Izuru is a gloomy and introspective person, not easily able to socialize with others. He generally appears weak and indifferent, leading many to believe he lacks the ability to be a leader. As an officer, he does not tend to inspire confidence or boost morale the way other lieutenants do. However, Izuru is loyal to both his friends and his duties. He also hates to fight unless prompted to or given orders. However, in combat he shows ruthless determination. His personality flaws are also assets: his introspection coupled with his tendency to worry makes him indecisive, but it also makes him sensitive to unusual behavior. Izuru's current personality greatly differs from his days in the Shin'ō Academy where he was shown to be much happier and slightly cocky after noting that Shūhei Hisagi had failed his entrance exam twice, whereas Izuru passed at the top of his class, giving him the idea that his talent was greater. Izuru likes to write haiku and he was also awarded for one of his pieces by Seireitei Communication, which is as follows: "The persimmon tree bears fruit. Aaah, the persimmon tree bears fruit again this year." His dislike for dried persimmon sheds some light on the background of the poem. He likes agar-agar instead. He also writes a serial novel titled "I Want to Apologize to You." It runs in Seireitei Communication and every new chapter begins with a haiku piece. He is also the author of Kira Izuru's Haiku Time. In his free time, Izuru participates in gatherings of haiku lovers. He also gives a special lecture of poetry on the Shin'ō Academy. It is also known that he is skilled in playing cat's cradle.