WARNING: The following contains spoilers for Episode 18 of How a Realist Hero Rebuilt the Kingdom, streaming on Funimation.
How a Realist Hero Rebuilt the Kingdom is an isekai about leadership and all the difficult and dangerous decisions that can entail. Souma Kazuya is king of the fantasy kingdom of Elfrieden, and his biggest challenges so far have been the civil war between its various duchies and the war with the Principality of Elfrieden. Episode 17 reinforced that one of Souma's opponents, Duke Castor Vargas, only turned against him because of his loyalty to Duke Carmine, whose opposition was in turn part of a secret plan to support the king. Even so, Souma still believed the dissenters had to be punished.
Realist Hero entered the courtroom genre in Episode 18 as King Souma oversaw the long-awaited trial of Castor and his daughter Carla for treason. Duchess Excel Walter spoke on the prisoners' behalf, while Prime Minister Hakuya Kwonmin fulfilled the role of prosecutor. The trial was also attended by a committee of nobles who served in a position similar to a jury, but Souma made it clear that he would be the one to make the final judgments.
Duchess Walter argued that the Vargases used their airforce against Souma out of loyalty to Carmine and the previous king. Hakuya pointed out that Souma was appointed by the previous king, meaning there was no excuse for the Vargases not to trust his judgment. Two nobles spoke out in the prisoners' defense: Piltory Saracen accused Souma of acting as though they had already been found guilty from the outset, and Owen Jabana argued that Castor should be forgiven so the kingdom could continue taking advantage of his considerable military aptitude. In contrast, other nobles encouraged Souma to execute the prisoners for opposing him.
Souma then made a shocking declaration of "kill them," and two mysterious assassins appeared behind Piltory and Owen. Two slices were heard alongside a closeup of Souma's face. This turned out to be a misdirect, as every noble except for Piltory and Owen had been executed. Souma explained the nobles in question were connected with Amidonia, and Owen surmised that they were siding with whichever power was most useful to them at the time. This is reminiscent of the Amidonian mercenaries who offered their support to the duchies and Souma in anticipation of the war in Part 1.
Souma once again used Machiavelli's The Prince to justify a "cruel" decision, arguing that it was better for a leader to be feared than loved. He would later lament, "I understand what Machiavelli is saying, but even so, I'm having second thoughts about whether it was the right decision." This makes it seem like Souma thought he had no choice but to follow his favorite writer's philosophy to the letter without independently developing it.
It was unclear if the nobles were guilty of a crime per se, but Souma believed they could be a threat to the kingdom in the future. This makes Souma's execution of them for having questionable alliances seem like an especially authoritarian exercise of power, punishing them for a crime they might commit rather than one they did. He did clarify that he wanted to protect his Elfrieden family from another conflict in the future, rather than a selfish desire to protect his own power. Even so, his judgment demonstrated how the kindest of intentions can lead to the most brutal deeds.
Afterward, Castor begged Souma to let Carla off more lightly because she was only following his orders, but Souma insisted on a harsher punishment because she didn't have his service record. He exiled Castor from the Vargas Duchy and put him under Duchess Walter's remand, then sentenced Carla to become a royal slave. Carla may have expected to be executed, but this was still a considerably dark punishment as anticipated by Realist Hero's Part 2 trailer.
As Castor was removed from the palace before hearing Carla's sentence, he begged for Souma to take his life rather than hers as he was escorted away. Could Souma have deliberately ordered his decisions this way to make Castor think his daughter would be executed? Given Carmine's execution, Castor's punishment could be described as relatively light. Perhaps Souma decided to exercise another brutal "cruelty" by emotionally punishing Castor, at least until he potentially discovers Carla is still alive.
Souma then quietly ordered Carla to execute him if he ever became a tyrant, knowing he couldn't expect the unwaveringly loyal Liscia and Aisha to do the same. His concern about potentially becoming a tyrant seemed especially pronounced given his execution of the nobles, and the way he frankly entrusted his fears of growing "drunk on power" to the prisoner ironically provided his most humble moment of Episode 18. Whether Souma becomes a tyrant as he feared or not, this was a turning point in the brutality of his rule in Realist Hero.
