When translating from Japanese, you need to consider how to treat honorifics: -san, -chan, -senpai, and so on. In a lot of pop culture, localizers have started just leaving them in and thus preserving their meanings; if your audience is Japanese pop culture aficionados, then you can trust them to understand. This works when the story is set in Japan, but it is odd when English butlers or medieval swordsmen go around calling people -kun.
In most cases, it is best to simply translate the honorific when it sounds natural in the target language, and drop it otherwise. Think about how the characters would actually address each other if English was their native language: classmates don’t use titles for each other, but adults are often called Mr. or Mrs. So-and-So.
Of course, the Ar tonelico 2 localization offers a middle-ground approach that results in the worst of both worlds. They translate every honorific, regardless of whether it makes sense. So, you get high school students calling each other “Ms.”, a senpai called “Master”, and so on. The dialogue ends up at least as awkward as it would have been with the Japanese honorifics, but without the nuances of the original words for people who know them. This policy continues throughout otherwise Japanese-culture-saturated parts of the game.
In our relocalization, we’re taking a hybrid approach. Almost everywhere, we translate addresses to be as natural as possible for native English speakers. But in the fantasy side-stories that take place in a fictionalized Japan, full of references to Japanese school life and popular culture, it makes sense to include the original honorifics. When the character is a moe-crazy otaku in a maid cafe, seeing him address someone as “-san” is not going to bring the story crashing down.
The official localization’s honorifics policy is odd for a game that included “moe” as a bullet point in its marketing.