Wasn't he supposed to never talk in the presence of Carlos?
I remember something like that from the novel.
Basically, it would mess with his blessing of words if he spoke Japanese or badly pronounced whatever language they speak there.
Either the author is a complete troll or an extreme ideological pacifist.
Sei's self persecution and the persecution of others towards him for even the lowest amount of aggression is disingenuous.
The characters are all complete wimps and there is zero believable psychology anywhere to be...