Kazuha is Heiji's childhood friend. She frequently gets angry at Heiji and often has arguments with him. Her relationship with Heiji is pretty much like Ran's relationship with Shinichi. Deep inside she cares deeply for him and worries about him whenever he goes out on a case. Kazuha even gave Heiji a good luck charm to carry with him to protect him. She is a close friend of Ran and wishes to see Ran's childhood boyfriend, Shinichi. Kazuha is also a master practitioner of aikido. Despite her tendency to argue with Heiji, she actually likes him.