Niki spends a lot of time on her own these days.
The study group was the most beautiful idea, but beautiful things don't survive here. Ever since Wilbur...ever since what happened, it's all been falling apart. She should have seen it coming, she was stupid to not see it coming, but she believed in what Wilbur...in a pretty idea someone told her, and it got all of them nowhere. Eret left them, Schlatt is dead (though she can't muster up much sadness for him), and Wilbur is...Wilbur left them too. Now Tommy is also as good as dead. The study group was something special and precious for a little while. It counted for nothing, and now it's nearly gone.
So Niki spends a lot of time on her own. She knows it isn't safe, but she doesn't especially care.
It doesn't help that no one wants to be around her. Eret stays with Tampa. Niki doesn't hate them anymore, or at least not as much, since the choice they made just hastened what was going to happen anyway, but they don't speak to her and she doesn't speak to them. Toby's so distracted by his own problems he can barely see beyond the end of his own nose, and ever since Tommy, he treats everyone like a problem-in-the-making. Alex doesn't care about anyone that doesn't have something he wants, and he and Niki don't like each other. She thought for a while that it was Schlatt making him worse, but Schlatt's dead and he still only cares about saving his own skin.
(Here's a secret Niki will never tell, not if she survives the Scholomance, not as long as she lives: Schlatt might not have died. She had more and better antidote than what he'd bullied out of her; she could have let him have it or even given it to him after he was poisoned, but she didn't. She hated Schlatt. She hated him taking whatever she had because he could, and she hated how Toby flinched every time he raised his voice, and she hated how Alex would hide bruises, and she hated how they all had to listen to him anyway because he was older and meaner and had resources they needed. She hated what he turned Wilbur into.
So she let him die. No one noticed because no one listens to her anyway, but she did it on purpose. Maybe that makes her a bad person, but she doesn't care. Everyone is a bad person in this place.)
The only other person left in the study group, the only person she works with now, is Jack Manifold. Jack is a good friend. He's angry at all the same things she's angry at.