The father of Sei Handa. He is an accomplished calligrapher that Sei has admired and respected since his childhood. He sends Sei to the Gotou Islands to reflect on his personal flaws after he punches an art director. Although seemingly strict, he is a doting father to Sei and describes himself as an awkward person.

Seishuu Handa is an up-and-coming calligrapher: young, handsome, talented, and unfortunately, a narcissist to boot. When a veteran labels his award-winning piece as "unoriginal," Seishuu quickly loses his cool with severe repercussions. 

As punishment, and also in order to aid him in self-reflection, Seishuu's father exiles him to the Goto Islands, far from the comfortable Tokyo lifestyle the temperamental artist is used to. Now thrown into a rural setting, Seishuu must attempt to find new inspiration and develop his own unique art style—that is, if boisterous children (headed by the frisky Naru Kotoishi), fujoshi middle schoolers, and energetic old men stop barging into his house! The newest addition to the intimate and quirky Goto community only wants to get some work done, but the islands are far from the peaceful countryside he signed up for. Thanks to his wacky neighbors who are entirely incapable of minding their own business, the arrogant calligrapher learns so much more than he ever hoped to. 
(Source: MAL Rewrite)

For a certain reason, a handsome, young calligrapher by the name of Seishuu Handa uproots himself and moves to an island on the westernmost edge of Japan. "Sensei," as he comes to be known, is a city boy through and through, and has never experienced rural life until now. And by the looks of it, he has much to learn! Luckily(?), he has a willing teacher in Naru, the energetic expert islander, to help show him the ropes. But can Sensei keep up with the plucky first-grader, or will he get schooled?! Here unfolds a heartfelt island comedy about a gruff on the outside, soft on the inside urbanite teacher and his new, unfailingly kind island neighbors! 
(Source: Yen Press)
 
Notes: 
- One extra and four side stories are included in volume 18+1. 
- Original serialization was completed on 2018-12-12 with 18 volumes (139 chapters). 
- A new limited-run serialization was started on 2023-04-12 and ended on 2023-09-12 in Monthly Shounen Gangan, in conjunction with the TV-drama adaptation. This new run adds 7 chapters and 1 volume to the total count.

Seimei Handa