She is sitting in the library, studying. It's her most common pastime, by hours; spending time with her sister is more enjoyable but Jaromira prefers to socialize more broadly and Katarzyna would only get in the way. This is better on net; the two of them share a room, so it isn't as though her sister's time is entirely hogged by the other girls who call this boarding school "home." Or at least "prison." Katarzyna doesn't mind it, though; the school library is excellent, and basic manners and care for the books has endeared her to the librarian to a sufficient degree to lubricate the interlibrary loans process when there's something she wants to read that they don't have.
Kanimir and Jaromira in Fabulous
"No, I'm totally on board with that--I have metamagic, I'm trying to explore what that can do, but even if my wildest hopes pan out I'm not planning to be a Paladin."
"I'm open to being persuaded but it'd take some persuading to make me go military."
"They're not military military but they're military enough to rub me the wrong way."
"Besides, fighting Kaiju is a noble practice, but I'm more academically than combatively inclined."