Honorifics: Jack

Jack refers to all the first-year students by their first names with no honorifics, no exceptions.

Jack usually refers to the second-year students as “first-name-senpai.”

He once asked Ruggie for permission to refer to him as “aniki” (for older brother, the same word Leona and Ace use to refer to their own older brothers), but Ruggie turned him down.

Exceptions: Jack never refers to Azul as “Azul-senpai” in Book 3 (and neither do Ace or Deuce).

Jack will add “-senpai” to Azul’s name in events and vignettes but usually after a long pause, as if he is simultaneously reluctant to be rude and reluctant to be polite (possibly lingering resentment from Book 3?).

He will generally refer to the twins with the “senpai” honorifics, but there is at least one instance of him dropping it from Floyd’s name, and during the Stitch event he gives Floyd the Azul treatment of a belated “senpai” honorific.

Jack refers to all the third-year students as “first-name-senpai.”

When Jack first reunites with Vil at his orientation he initially refers to him as “Vil-san,” which is possibly what he called Vil back in his hometown.

He corrects himself, changing to “Vil-senpai,” which is how he refers to Vil throughout the main story, events and vignettes.