Reimu
A shrine maiden who resolves incidents and manages the Hakurei Border. Reimu is intuitive, optimistic, fairly straightforward towards people, and can be rather curious. Highly devoted to her duties, she secures the land with her clan whenever threat arrises.
Reimu was born in a time where the name "death cheater" was long forgotten. Hence, she was never told about the Death Card, nor about those who used it against her clan. Kids who visit the shrine sometimes tell her stories about "People who laugh at death with immortality", but Reimu simply brushes it off and tells them not to believe such nonsense.
With the appearance of Matilda, this could be the Hakurei's greatest incident yet. For Reimu, it could lead to a past where she never knew existed...
Alice
A magician with the gift of making and manipulating dolls. A secretive and confident person, who is mostly indifferent to the people she meets. Alice is greatly attached to magic, and often embarks on journeys that take her deep into the mystical areas in Gensokyo.
In one of her travels, she stumbled upon a Death Card in one of Gensokyo's many forests, presumably drove it's previous owner ironically to suicide. Terror and excitement filled her heart, as she could not believe that in her hands was a power that once could have destroyed half of Gensokyo. Infinitely fascinated by this dark power, she now spends her time researching anonymous information about the death cheaters in the Forest of Magic. She authored a manual called "How to Become a Card Wielding Death Cheater", despite knowing that may never find an audience.
Alice has committed to finding someone, anyone, who holds another one of these forbidden powers, risking the dreaded thought of being exposed to the Hakurei while at it.
Marisa
An ordinary human who learned the power of using magic. Her self-indulgance and disagreeable nature would take her to places where most people would not dare step foot in, leading her to many conflicts and treasures in Gensokyo's more obscure regions.
She frequently visits the shrine to see what the Hakurei are doing, and "accompanies" Reimu in solving incidents (not necessarily by permission). She is also neighbors with Alice, and is the only one aware of Alice's recent discovery. Marisa constantly tells her to get rid of the Death Card before something terrible happens, despite her own curiosity for this dark power.
Minister Wayzer
Long seen as a laughable, but still somewhat dangerous nuisance to the Hakurei, Wayzer collaborates with unknown organizations and cults to practice dangerous magic. Though it is unclear what exactly his goals are, and why he is always trying to threaten the Hakurei. His plots are usually foiled by Marisa as they both end up going to Gensokyo's more obscure regions by chance.
A true coward when it comes to fleeing for himself, yet is a master of persuasion when it comes to making deals with strange and shady creatures. He is trying to revive some kind of ancient demon, but is ambushed by the Hakurei and Marisa yet again.
Matilda
An entity who believes is destined to become Gensokyo's symbolic ruler of peace, and convinced the only way to do so is to destroy the Spell Card system along with the Hakurei who refuse to pledge loyalty. Not much is known about her, where she comes from, or what she looks like. Perhaps she is preparing a grand entrance while she sends her loyalists to speak on her behalf...