Hinoki Morino, known as Harold Miller in the English dub with his initial preserved, is one of the Morino quintuplets and sibling to Kabuto, Arashi, Kinoko, and Kodama. As the family bookworm, he aspires to win a Nobel Prize, with his academic focus central to his identity. He engages with intellectual challenges, such as exploring a ghost theory and attempting to deal with an obake. His desire for privacy and quiet is highlighted in an episode centered on securing a personal space. Hinoki also demonstrates an interest in unconventional topics like fish prophecy. Despite his scholarly nature, he participates in activities such as a sumo wrestling tournament, showing his willingness to join varied endeavors alongside his siblings. He contributes to the family’s collective adventures, which often involve collaborative problem-solving.