Character

This article lists characters in the SS undefined.

Other

 * Denizens of the deep.
 * Sally and Hara Wataru, a pair of graffiti artists.
 * Marie mentions having a friend who is a blackbelly skate.
 * Marina mentions that her landlord is a narwhal and one of her friends is a sea sponge.
 * A handful of animals are seen and/or heard at various locations, including seagulls, sparrows, cicadas, and crickets. Unlike other creatures in Splatoon, many of which have evolved into more human-like forms, these animals seem to have changed very little over time.
 * Shy-Ho-Shy, the Squid Sisters' producer. She was a judge at the Youth Folk-Singing Contest, where Callie and Marie's performance caught her attention, which led to her becoming their producer. She created a demo of City of Color as a reference for the Squid Sisters during the making of the song, which is in Splatoon Live in Makuhari -Shiokalive-. Splatune 2's booklet contains an interview with Marina which mentions that she has been in touch with Shy-Ho-Shy.
 * Barry C., the owner of Hotlantis.
 * Glen Fiddler, the creator, CEO, and president of the Battle Lobby.