I dunno much about this IP but Djeeta doesn't exist in the anime right? She is the MC if you choose to play as a female?
And the anime stupidly went with a male MC?
And the game is ios/android only game you have to buy unlocks with real money etc?
I assume nothing develops between the female MC and any other girl in the game? I heard she becomes life bound to another girl, whatever that means.
So at the beginning of the game you meet Lyria, while protecting her from a guy named Pommern (Pommeryn? I forget it's been a while since I last saw him.) who wants to lock her up in the name of the Erste empire for experimentation you end up getting fucking murdered by his Hydra summon. Lyria basically goes "Fuck no" and binds you to her so that you live but this has the consequence of neither being able to be very far from each other.
Gran is technically the canonical protagonist but the game will change some dialogue if you play as Djeeta instead.
It's definitely possible to play the game without spending any money and they give a lot of free stuff out to everyone (currently there's a free draw every day). Spending money allows you to get cute outfits, pick characters, and/or get extra rolls without spending crystals.
While there isn't much romance for the protagonist there are several characters that canonically pair up or are interested in each other. Some of the yuri includes, Vira likes Katalina (and is totally Yandere for her), Orchis, Appollonia, and Orchid all like each other, I got a maid who's definitely after Lyria a while back, and Freesia is super into Orchis' mom which has some interesting consequences to it. (Not technically a romance but I found it hilarious Nene mistakes the protagonist for her vanished husband- even if you're playing as Djeeta, and when Lyria points it out "Captain's a girl though!" and Nene grumbles that that's something she's pretty sure her husband would do to try and get away from her)
Frankly all the characters are really fun and have their own personalities so it's a lot of fun to level them up since you get to see more of their story.