[My favorite official art of this duo!] (Warning: Some of them whitewash Marina. I hate it here.)
Off the Hook are the idol duo featured in Splatoon 2, consisting of Pearl and Marina! The pair hosts Inkopolis News and Splatfest events, with one of the two representing either side of the Splatfest. Of course, they also release music together! In the original Japanese text, it is much more obvious that the two are romantically involved, or, at least, romantically interested in each other; this is explicitly confirmed on Marina's part in the relationship chart (although it's implied through dialogue that it's not one-sided). However, all English localization of Splatoon material censors this.
Marina was previously born into the Octarian army, but, upon hearing the Squid Sisters sing the Calamari Inkantation from Agent 3's battle against DJ Octavio from Splatoon 1, she is able to break from the brainwashing and desert the army. She ran away to Mount Nantai, where she met a li'l emo Soundcloud rapper and it was all over. She didn't even speak the Inkling language, but, upon hearing Pearl practicing singing, the two quickly grew on each other, and, soon after Marina showed off her own musical abilities, they formed Off the Hook together. 9 months after the events of Splatoon, they had become popular enough to take over hosting Inkopolis News from the Squid Sisters, who were now off on solo careers. In the meantime, Marina pretends that she is an Inkling around everyone else, including Pearl, fearing that others would reject her if they knew she was an Octoling.
Off the Hook consistently appears in Splatoon 3's Octo Expansion, helping Agent 8's journey along with Cap'n Cuttlefish. Cuttlefish, Pearl and Marina all communicate in a groupchat, which the player can read. It is in this groupchat the Cap'n Cuttlefish outs Marina as an Octoling, but Pearl, while shocked at first, jumps straight to her friend's defense, immediately threatening Cuttlefish if he tries to do any harm to Marina. Once Marina finds out she's been outed, she goes silent, but, upon being told by Pearl that she's still accepted, she's implied to start crying out of happiness.
Marina hacking into tech to help out Agent 8 becomes a pivotal skill in the later parts of the game, and both she and Pearl both play a huge part in Agent 8's final battle against Commander Tartar. Marina again uses her hacking skills to determine how to weaken Tartar's blast of primordial ooze from going off and destroying all Inklings and Octolings. Once that has been completed, Pearl uses her Hypersonic Battlecry to push back against the statue's blast, destroying it in the process.
By the events of Splatoon 3, the two have joined up with more band members, forming Damp Socks feat. Off the Hook. The pair are set to play a major role in Splatoon 3's upcoming paid DLC, Side Order.