Kazuhiko Osawa is Hikage Miyakawa's homeroom teacher at elementary school. He wears glasses that completely obscure his eyes and has khaki-colored or brown hair cut to ear length. His eye color remains unseen behind the lenses.

When approached by students, especially those in distress, he offers support with the consistent caveat: "Feel free to talk to me, as long as it's not about money," reflecting his avoidance of financial topics. He presents himself as a generally gentle and approachable instructor. However, his advice is often generic and lacks practical utility for students facing specific hardships like poverty. He notably misinterprets Hikage's excitement about seasonal sales as anticipation for Christmas festivities.

His role involves minor continuity-based interactions, such as referencing prior conversations with colleagues concerning students like Erika Koike. He remains a static supporting character, fulfilling his function solely as an educator in Hikage's school life, without significant personal background, development, or expanded narrative.