I don't get it that sleeping with Nika is out of Maja's character thing. So far all the facts clearly suggest that she is a total nymphomaniac. From being one of the founders of the free titty movement in college to having 3 boxes of stockings, 4 of corsets, 5 of latex, 7 of sex toys and 8 of BDSM accessories. Right now it's safe for Vik because she doesn't find Nika sexually attractive to her but when that changes it's going to be a tough fight with her crazy sexual urges
100 % Nympho always stays 100 % Nympho
Actually, Maja is all about control. What is her fetish? Shibari. Chances are she likes doing they tying seeing she's always in braids. But think about her box of sin; after all, Maja's got a lot of toys. She KNOWS how to satisfy herself without a dead pocket rocket. She's also creeped out by NIka having used any of it. So she's not a dirty nympho at all. She is (at least so far) depicted as someone who has specific tastes and knows what she wants.
All her interactions with Nika suggest that she's mostly tolerating him for Vic's sake. Keep in mind, Nika has an incredibly dub moment when he starts talking with her the first time, acting like a trenchcoat dude. She's suspicious of him being a creep. But the very next thing for her is Vic being obsessed with this guy, and Maja being responsible to look after Vic. Vic wants Maja to find him, because Vic keeps telling Maja about him. Vic wants all kinds of romantic moments that she fantasizes about that she tells Maja. Maja knows it will break her sisters heart if Maja takes him from her. She's the one in charge of keeping Vic stable/happy/looked after also. So even if she finds Nika attractive, she has to overcome her loyalty to her injured sister.
I can safely say her impression of NIka isn't anywhere near the level that it would overcome her loyalty to Vic.
So, if Ocean plans lewds, it will be a moment of weakness most likely. Instead of her attraction being so high, her will is lowered, by circumstance or alcohol - remember she left Vic with a bottle to loosen the stick up Nika's ass. Or because she's stressed out trying to pay the way of all the medical bills for Vic, and just has a moment of weakness. That is the only way I can see it happening, and then, most likely only if you reject Vic's date - Maja is HELPING Vic plan her date.
Horniness isn't the only force of gravity in the world. There are other bonds.
At least, that's what's been characterised so far. Whether or not OCean thinks about it this deeply is another matter - after all, every one of Ocean's girls seem to be going to the same body piercer lately, so it's still Ocean logic we'll find out about.
For me, the possibility that there is some Maja content might be part of the manwhore path, where you end up missing out on LI's by playing the field.