Kaguya was once the princess of the Lunarians, a race of people living on the Moon. She was exiled to Earth over a thousand years ago for the crime of using the forbidden Hourai Elixir to make herself immortal. Arriving on Earth in what is today central Japan, she was found by a bamboo cutter and dwelt among the humans she had once despised. Though the Lunarians looked upon humans with contempt, Kaguya came to love her new home. Her unearthly beauty led men from all across Japan to seek her hand in marriage, but none could successfully complete her trial of the Five Impossible Requests. After years of exile, emissaries arrived from the Moon; Kaguya had been forgiven of her crime and it had been decided that she should return. Kaguya, however, had grown to love life on Earth and had no desire to return to the lunar capital. Enlisting the help of her friend Eirin, Kaguya escaped from the emissaries and fled to Gensokyo. Taking refuge in an ancient mansion called Eientei hidden deep within a secluded bamboo forest, the two Lunarians began a new exile. During the events of Imperishable Night, Kaguya had been hidden in a secret pathway along with the true moon by Eirin to ensure any Lunarians sent to recover Reisen would not discover her. The heroines, however, did discover her, and challenged her to return the full moon to Gensokyo. After being defeated, Kaguya unleashed her power of eternity in an all-out bid to break the spell of the imperishable night cast by the heroines. Finally she relented and the true moon was recovered. She now spends her days living in Eientei in a carefree manner, sometimes holding exhibitions of Lunarian treasures there for the rest of Gensokyo to admire. Her long isolation has made her lonely, and she enjoys telling stories to any guests she might receive.
Youmu is one of the stranger entities in Gensokyo, part-human and part-ghost at the same time. Her two halves are not intermixed like one would expect from a cross-breed, but actually exist in physically separate bodies. Youmu has a straight-forward and focused personality, which complements her swordsmanship abilities well. However, her personality conflicts with that of her master, Yuyuko Saigyouji, who is very whimsical and playful in nature. Still, she serves Yuyuko as best as she can, tending to the gardens in Hakugyokurou and following her orders. Youmu commonly wields two blades at once, having studied some under her father, Youki. The longer blade, called Roukanken (Tower-Watching Sword) is said to be able to kill ten ghosts in one swipe; the shorter blade, Hakurouken (White Tower Sword), is able to cleave through a person's own confusion. However, not much is known about her particular style of swordsmanship, or her parents. What is known is that Youki, also a servant of Hakugyokurou, had begun training a very young Youmu when he suddenly disappeared one day, leaving her style incomplete. No one currently knows his whereabouts. (Source: Touhou Wikia)
An intelligence broker who helps Odajima dig up information on Reiji.
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. (Source: Hana to Alice: Satsujin Jiken)