Mineaki Irido is the father of Mizuto Irido and stepfather to Yume Ayai following his marriage to her mother, Yuni Irido. He raised Mizuto alone after his first wife died in childbirth. Mineaki is a workaholic, frequently absent from home due to work commitments. Despite this, he is a good parent and part of a happy marriage with Yuni, who is a supportive stepmother to Mizuto. Neither Mineaki nor Yuni know that Mizuto and Yume dated during middle school.

The Irido family exhibits a naming theme: Mineaki and Mizuto share the "Mi" sound, while Yuni and Yume share the "Yu" sound. Mineaki's name combines the kanji for "peak" (峰) and "autumn" (秋). His surname "Irido" uses characters meaning "that one" (伊), "reason" (理), and "door" (戸). Physically, Mineaki has messy black hair and brown eyes.

Mineaki's extended family includes his mother, Grandma Natsume, and relatives like Madoka and Chikuma Tanesato. During a trip to the countryside to visit Grandma Natsume, Yuni and Yume met Mineaki's family for the first time, illustrating the blending of the family unit. Mineaki's depicted role centers on his responsibilities as a parent, with his personal backstory limited to his remarriage and parenting.