Given names paired with an epithet (Rin, of the Ninth Ward) because a title is what turns a name into a character.
A given name on its own is just a name. Rin tells you nothing. Rin, of the Ninth Ward tells you there are wards, that they are numbered, that belonging to one is worth stating, and that this character is defined by where they are from. The epithet is doing worldbuilding in four words, which is why the convention is so common in the genre and why a generator that produces only given names is far less useful than one that pairs them. Turn the epithet off when you need a plain roster and on when you need characters.
A generated name is a prompt, not a decision. The useful move is to take one that produces a reaction and ask why, if the Last Cartographer suggests a character to you, that instinct is the actual output and the name is just what triggered it. Names that arrive with a built-in question are worth more than names that merely sound right. For roleplay servers and tabletop campaigns, generating a handful and picking the one that raises a question you want to answer is a faster route to a character than starting from a blank sheet.
No. Given names are drawn from a general bank and paired with invented epithets, so the results do not reproduce existing characters.
Yes. Switch it off for a plain list of given names, which is what you want when populating a background roster rather than designing a character.
They are common romanised given names, presented without kanji. If the spelling matters for your project, check the reading with a native speaker.