- More than a few fan works portray Callie and Marie as adopted siblings due to the fact they're biologically cousins yet their idol duo is named "Squid Sisters." This is usually in conjunction with them being raised by their grandfather. Splatoon 2 supplementary material implies otherwise, with one chapter of "Squid Sisters Stories" having Marie visit her parents, but since Callie's aren't mentioned, this fanon isn't seen as officially jossed.
- Pearl's short height, immature personality, and unusual design (including a single pointed tooth, only seen in prepubescent Inklings) initially caused a lot of fans to theorize that she was Younger Than They Look. This was eventually jossed when she was given a canon age of 21, pinning her as Older Than They Look.
- Pearl as Sir Swears-a-Lot due to her tough personality and her career as a rapper. In an odd turn of events for a Nintendo game, the Octo Expansion confirmed this by introducing one of her old songs before she and Marina formed Off the Hook, "#$@%* Dudes Be #$@%* Sleepin". The song is a faced-paced heavy metal Cluster F-Bomb, with a prolonged Sound-Effect Bleep on top of it all.
- Marina is seen as having a Dark and Troubled Past as a high ranking ex-soldier for the Octarian army who escaped to the surface. Canon would later confirm that while she was part of the army, she was an engineer rather than a soldier. Fanon also depicts Marina as having grown up poor, in contrast to her wealthy best friend Pearl and as part of the wider fanon of Octolings living in destitute conditions in comparison to the more carefree Inklings.
- Considering that Inklings are evolved squid, they're generally viewed as laying eggs. Octolings, Jellyfish, and the other species are the same way.
- Certain punny slang and profanity is widespread amongst fans. For example, Inklings say "squit" instead of "shit".
- Marina and Pearl are roommates. Most of the time they're also in a relationship, though occasionally they're just friends. In the English translation, Marina has implied that she lives by herself.
- Before the Octo Expansion, fans generally assumed that everyone knew Marina was an Octoling and that (most) didn't care. In canon, few people outside of the New Squidbeak Splatoon are familiar enough with Octarians to recognize that she was one, and most just think that she is an "exotic" looking Inkling. Even her partner Pearl, while it was implied that she at least had suspicions, never knew how to talk to Marina about it until the Octo Expansion.
- It was assumed throughout the original Splatoon that the characters were much smaller than adult humans. Marina's height in supplementary material of the second game, however, reveals that everyone is to human scale.
- Marina is bilingual and she speaks with an accent. This comes from the Japanese version, where her speech is occasionally rendered in katakana, which is used by other Octarian characters to indicate that they are speaking a different language. Her ordinary speech is only partially rendered this way, implying an accent of some sort, while her lyrics in Off the Hook's music are entirely in katakana, which indicates that she's singing in Octarian. Likewise, her speech in the Japanese version is often overly formal, and she tends to make many malapropisms, further indicating that she's only recently learned the Inkling language.
- Marina is often theorized to be directly related to DJ Octavio, as the two are both Octarian DJs. In canon, while Marina was a high-ranking officer serving under Octavio in the Octarian military, her backstory makes no mention of any relation to him. Furthermore, DJing doesn't seem to be all that uncommon among Octarians, as we later see in artists like Dedf1sh, PAUL, and Warabi.
- To reconcile her Japanese and international personalities, many fans saw Marina as a Shrinking Violet who only acted sarcastic and sassy while on-air to compensate for how nervous she really felt as an Octoling integrating into Inkling society. When the Octo Expansion later gave fans a better look at Marina's off-screen personality, it confirmed that this was almost exactly the case.
- It's implied that Callie and Marie were 17-18 in the first game, but most interpret them as being in their early 20s instead.
- The violinist of Bottom Feeders is feminine looking but looks like a male Betta fish. Fan consensus is that they're either a effeminate looking male or a transgender person.
Fanon / Splatoon