Kiru-Beam

The Kiru-Beam (キル光線,) is the primary weapon wielded by Kiruko throughout the events of the Heavenly Delusion series.

Profile
The gun's range is quite limited at only 5-6 meters according to Kiruko. On battery power it can only fire up to 4 times with the 4th shot not even being guaranteed to fire. Kiruko mentioned that while the gun is powerful in nature, it takes nearly 30 seconds before it can fire after the gun is turned on.

The gun is damaged while Kiruko uses it. It is suppose to have a cover that was blown off of it and be wired to an energy pack that the user is meant to carry with them. These two aspects are likely responsible for the gun’s limited range and ammo capacity.

Usage
The specific “Kiru-Beam” seen throughout the series traded hands multiple times before ending up in Kiruko's possession. Before her it belonged to Mikura. The gun was originally smuggled out of Takahara Academy by the child Mako.

Trivia

 * The series author shared on Twitter that he actually owns a life size version of the gun which he uses as a drawing reference. He (assuming the translation was correct) actually had it made before the series began publication.
 * It's also known as the "Murder Beam" in fan-translations of the manga.