Sajuna has that small, youthful look going for her—pale skin, pale pink hair styled half in pigtails and half long, and these big hazel eyes with really long lashes. She's usually dressed in a red sailor suit with a yellow bow and black knee socks, which pretty much defines her whole aesthetic.
Her personality's a bit of a contrast to her cute appearance. She's headstrong and blunt, quick to snap at people and not afraid to speak her mind harshly when something bothers her. Cosplay is something she takes seriously; she genuinely loves it and the characters she dresses up as. What's interesting is that despite having a decent online following, she doesn't care about the fame side of things. She's made it clear she cosplays purely for herself, not for attention.
She's the type to go all-in on something she wants, and while her default mode is pretty gruff, she's perfectly capable of being genuinely kind and friendly when she lets her guard down. She and Wakana ended up getting along, same with Marin, and she clearly cares about her younger sister Shinju. There's a softer side there, even if she doesn't advertise it.
One thing that doesn't fit her tough exterior is that she's actually afraid of thunder and scary places, though she tries hard not to show it. Being at an all-girls school, she's also pretty inexperienced when it comes to guys. She tends to hold back about how she really feels about things, which gives her that tsundere vibe—the whole defensive exterior hiding what's underneath.
Content compiled by AnimeList.moe from publicly available sources.