I hate when TL use untranslated words like we should know what they mean. If we did, we wouldn't need a translation then, would we?
Last chapter the old guy kept using "Nobu" like it was someone else's name ("Nobu's martial arts","Nobu's techniques", etc...). I though it was his founding ancestor or something.
NOW we get a PR note that explains he's just refering to himself.
Where any other translation would write "this old man", this translator just use the korean word leaving it to the PR to do their job (barely, as it should be corrected instead of adding a note).
Some people never learn...