Lapis Blade

Please keep your serial killers in their own centuries. One is bad enough. Four in one body is the definition of 'nope.' Add in what amounts to a demon and you get nope squared.

Lapis Image: By This file was donated to Wikimedia Commons as part of a project by the Metropolitan Museum of Art. See the Image and Data Resources Open Access Policy, CC0, https://commons.wikimedia.org/w/index.php?curid=60925577