Heiji Hattori and Kazuha Toyama

Background

Heiji and Kazuha have been friends since they were little kids, and have remained close throughout the years like Shinichi and Ran. They are a high school detective and a detective's daughter, which is also like Shinichi and Ran. They always bicker and make fun of each other, but they do have a soft spot for each other like best friends should. They also show hints of romantic feelings in the series, and everyone calls them a couple including their parents, Ran, Shinichi and others who see them together. However, they deny that they have any romantic interest in each other. They have gone together almost everywhere in the series and have gotten into danger together like when they were kidnapped. Heiji clearly shows that he is very protective of Kazuha from other guys (much like Shinichi is with Ran) but he only thinks of it as protecting his friend. Kazuha says she is like his much more mature and wise older sister. In the 7th movie of the series, Heiji discovers that his first love was Kazuha.