WARNING: The following contains spoilers for Episode 25 of How a Realist Hero Rebuilt the Kingdom, now streaming on Funimation.
How a Realist Hero Rebuilt the Kingdom is an isekai that makes the most of the genre. Japanese high school graduate Souma Kazuya often uses real-world politics as a guide as he rules the fantasy kingdom of Friedonia. In Episode 25, Souma was also shown to have introduced two home comforts from Japan to the kingdom.
Souma grew excited when Poncho recreated one of his favorite Japanese condiments. Later, he and his fiancée Princess Liscia sat under what appeared to be a Japanese kotatsu. Souma rarely talks about his life before being summoned to the kingdom, but Episode 25 revealed he may think about it more than he lets on.
As Souma discussed the refugee population in the city of Venetinova with Prime Minister Hakuya Kwonmin, resident culinary expert Poncho Panacotta burst into his office to announce that he had completed an important project. Hakuya stayed behind as Souma gleefully tasted Poncho's latest concoction: "a sauce for flour-based dishes," such as okonomiyaki. King Souma was thrilled, praising Poncho for how accurately he had recreated the Japanese condiment. It's notable that while he has been dedicated to solving important social problems like poor hygiene and unemployment while trying to raise morale with public works, nothing has made him more exuberantly happy than tasting his favorite sauce again.
Remarkably, Hakuya described it as "unlike ordinary Worcester sauce," another fermented condiment. This line implies that Worcester sauce exists in the world of Landia, despite its eponymous English county of Worcestershire not existing there. This is likely a quirk of how the continent of Landia's fictional languages are translated for Souma's ears and the audience, but it is still an interestingly similar juxtaposition to how Souma himself and Poncho have transplanted recognizable Earth food to Friedonia.
Souma generally appears not to miss Japan a great deal. This is likely due to his last living relative -- his grandfather -- having died shortly before he was summoned. The man also taught him to start a family of his own to protect, which he has found in his Royal Court and, perhaps, even the people of his kingdom by extension. However, Episode 25 revealed Souma may be more homesick than he appears.
The refugee Komain accused Souma of not understanding the refugees because he had a country to call home. Souma calmly responded that he also had a home he couldn't return to. Liscia expressed sympathy, perhaps having not considered Souma's situation from this perspective either. It's understandable that Souma would generally keep his homesickness to himself, prioritizing the responsibility he has to a whole kingdom of people. However, scenes like this remind the audience that leaving behind the country he grew up in is not so easy.
This was not the first time Souma expressed nostalgia for Japan. In Episode 4 of Realist Hero, he commissioned Poncho to prepare accessible new meals for a starving population. Poncho introduced him to "mashwater," a sauce that was identical to the soy sauce of his world. When Souma tasted mashwater locust, he couldn't help but cry in nostalgia.
Episode 25 closed with Souma and Liscia eating oranges as they sat at a kotatsu. In modern Japan, a kotatsu is essentially a table covered by a blanket with an electric heater underneath. Souma's Friedonian kotatsu could have been powered by charcoal like the earliest Japanese counterpart, or perhaps by the explosive "curse ore" that Genia Maxwell described in Episode 19 -- or even the fire magic that makes Friedonian technology so different from Earth's.
A kotatsu is a warming and comforting presence, and a fixture of many Japanese homes. It is understandable that Souma would want to preserve this sense of warmth and safety in his often turbulent life in Friedonia. He told Liscia that he’d "always wanted" to relax under a kotatsu. This humble aspiration surprised Liscia because it was a departure from the fantasies Walter had discussed during their class, but perhaps his simple remark also revealed a subtle desire to return to Japan.
Souma is not an engineer, so it makes sense that the modern ideas he brings from his world are political rather than scientific. Given his serious dedication to the kingdom, it's an endearing trait that the few inventions he has recreated are familiar comforts of life in Japan that bring him simple pleasure. Even so, Souma may miss Japan, but Realist Hero's protagonist still wouldn't want to be anywhere else than in Friedonia with his family.
