Demon Guns: Bolverk

Arcus Diabolus: Bolverk is a Nox Nyctores in the shape of a pair of handguns. It is the main weapon of Noel Vermillion.

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Bolverk can attack targets through walls, Type XI: Optic Barrel being a dimensional collapse of sorts at a point in line with the barrel. It also serves as a limiter for Noel as it suppresses her emotions, explaining why she does not become emotionally unstable, unlike Carl Clover or Jin Kisaragi. It is also revealed that in Noel's past, while she was being attacked by a monster, Bolverk appeared suddenly right before her. Noel's emotions can break Bolverk, unleashing her true persona. Bolverk is later restored - it is unknown how it happened.

During the Dark War, Bolverk had a multitude of owners, including Three of the Ten Sages. After their death, Bolverk was given to so many owners over time, its location eventually became unknown to even Jubei until its possession by Noel Vermillion.