Well-meaning, Ignorant Strangers
Tritons are nobles of the deep and champions of good...that understand very little of the surface world and its citizens. Though they mean well, they can often frustrated by others, quick to boast about the greatness of their civilization or phrase requests as orders intended to be followed. Choose a quirk in Volo's Guide to Monsters or think on it and make your own.
First-party race traits for the Triton can be found on page 116 of Volo's Guide to Monsters and is copyright Wizards of the Coast.