The Catholic Church is a location in the Raidou Kuzunoha duology.
As a proper Catholic church, the place is somewhat of a rarity in The Capital, and indeed, adding the fact the church is tightly gated for most of its appearances, it lies mostly abandoned. In Raidou Kuzunoha vs. The Soulless Army, it is mentioned it was once the property of a foreign merchant named Elfman. Near the church proper there is a small graveyard, most likely intended to house the church's few parishioners.
Seeking Elfman while searching stolen cargo from Harada Co., Raidou Kuzunoha the XIV infiltrated the church's graveyard, and found that Elfman had been murdered and his estate appropriated by Rasputin. Dispelling Elfman's ghost, Raidou confronted Rasputin at the church, after accidentally overhearing a conversation between him and his superiors by standing next to the church's confessionary. The Dark Summoner was defeated there, but soon rose again.
Later, during the events of Raidou Kuzunoha vs. King Abaddon, Louis Cyphre contacted Raidou with some frequency, posting Case Files for him to return to the Church to confront several Fiends. Mot also manifested himself at the Church, and his plans to return to the mortal world were destroyed there.