Hana Arai is the second main lead and deuteragonist of Hana to Alice: Satsujin Jiken. Alice ends up trespassing into Hana's house as she seemed to be part of the key to solving this "Juda" mystery.
Hana is a far more observant and thought-out person to counteract Alice's propensity to jump into any situation without much thought, at the mercy of her own whimsical nature. This isn't to say that Hana herself isn't a whimsical person; she very much is, she just keeps herself in check most of the time.
Where Alice is comparatively idealistic and childish, Hana is more than a tinge jaded, cynical and a tad bitter. Hana expresses most of her cynicism through deadpan humour; she is a deadpan snarker.
As it turns out, Hana dropped a bee down Juda's shirt on a whim because she felt irritated with him, which ended up stinging him and giving him an anaphylactic attack. This event ironically scarred Hana more than Juda, as she isolates herself to her house for most of the time after said event. It's likely because of this experience that Hana decided to keep her whimsical nature in check and think things out a lot more thoroughly before doing them; she contents herself with sticking at the sidelines and observing things before making a move; she represses herself.
It's through her interaction with Alice that she starts to rediscover a lot of her whimsical nature comes to light again. Alice pushes Hana forward again by forcing her to interact with Juda, as opposed to running away from her problems (i.e. Juda). Hana's relationship with Alice allows her to grow as a person and confront the things she was previously unable to face head-on; she gives Hana the strength that she can't summon on her own. Because of this, Alice becomes an important friend to Hana by the end of the film.
