In the Touhou world, Rabbits (兎, usagi) living in Gensokyo seem to be able to cast attack magic naturally. Also, a rabbit can become a type of youkai after existing for a long period of time, gaining sentience and increased abilities in the process.
There are also Moon Rabbits (月の兎, tsuki no usagi) who seem to be more powerful overall than normal rabbits. Moon rabbits seem to be used as capable soldiers in the Moon's war effort, and can communicate telepathically between each other across extremely long distances (like from the Moon to the Earth). In the Touhou world, the use of rabbits as part of the Moon's population comes from ancient tales in East Asia, possibly related to the fact that ancient Japanese people saw a rabbit in the moon pounding mochi, as opposed to a smiling face (the "man in the Moon").
Even though they may have a humanoid appearance, you can identify earth and moon rabbits alike by the two elongated ears on the top of their heads. As pictured at right, it is notable that all of the Eientei rabbits seen in Silent Sinner in Blue are humanoid, but the ones in Inaba of the Moon and Inaba of the Earth are all in their animal forms (except for the main characters).
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