Isanari Uesugi (うえすぎ いさなり, Uesugi Isanari?) is the father of Fuutarou Uesugi and Raiha Uesugi.


He has a distinctive golden, spiky hair with a bulked up and muscled body. Fuutarou five years ago also shared similar facial traits to Isanari.

He is always seen wearing sunglasses on his forehead. They are a memento of his deceased wife, who had bad eyesight while she was alive.[1]



Isanari has a wild character. Fuutarou five years younger is said to share the same personality as his father, notably both were bad at studying.


Fuutarou Uesugi

Raiha Uesugi

Maruo Nakano

Isanari and Maruo had a history of rivalry during school days, stemming from their differences. While Maruo was an exemplary student, Isanari was rebellious.[2]

It was through Isanari's connection with Maruo that his son, Fuutarou, became a tutor for the Nakano quintuplets.

Rena Nakano

Isanari and the quintuplets' mother, Rena, knew each other during school days. She was his senior, or senpai (先輩?), as Isanari addressed her.


  • "This is once in a lifetime event, don't you think that you could still make it?"



  1. ^ a b Character Book Itsuki page 63
  2. ^ Manga Chapter 103.
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