Spoiler Alert: WARNING! This page happens to contain a lot of heavy spoilers that are all originated from the Overlord Light Novel series written by the author Kugane Maruyama. To every Anime-only watchers and Manga-only reader out there viewing this warning, please mindfully consider your decision first before choosing to expose yourself on reading the information below. If you're not currently up-to-date with the main source material in the official books, do consider staying away from the page for non-spoiler sake until you actually read it first ahead of time.
Blade Bug (剣刀蟲) is a special insect found both within YGGDRASIL and the New World.
The Blade Bug can be used as a melee weapon when it attaches itself to the back of the user’s hand. When it wraps around its user's arm, it can shape shaped like a broadsword.[1]
Trivia[]
The Light Novel never indicated that the Blade Bug was an aerial insect, but in the Anime it is.