Colorless December

The Colorless December (무의 십이월, Mooeui Shibeewol; "The Twelfth Moon of Nothingness") is a 13 Month Series created by legendary craftsmaster Ashul Edwaru for the Princesses. Together with its owner, Eurasia Enne Zahard, it's sentient form was found in a maniacally psychotic state. Thus, both of them were sealed away. There is a rumor that this weapon drives the wielder insane should they not be the right owner.

Trivia

 * It is unknown if the weapon drove the Princess insane or if it was the other way round. And if so, how or why. It is also unknown if an external factor was instead responsible for the state of the weapon and its wielder.