He is voiced by Hiro Shimono in the Japanese Version, Micah Solusod in the English Version and Anthony Steven San Juan in the Filipino Version.
He have dark green hair, along with a piece of hair pointing up and blue eyes.
Haruhiko is very kind and strongly fascinated with books, and often reads them in the library.
Due to the library that in his house, he has a lot of knowledge about different subjects, but most of those facts are seen as useless by his teammates. His parents are separated but he hopes for them to be reunited as a family again. In the anime, most of the episodes begin with Haruhiko giving a brief explanation about certain topics.