Demon's Ring

The Demon's Ring (魔王の指輪) is a ring created by Velzard that is given to each member of the Demon Lord Council.

Demon's Ring allows to make "Cross-Spacetime Communication" with other Demon Lords. It has the secret call function for individuals, and also the ability to make a group call. With it, it is possible to make calls even from "Infinity Prison". The one drawback it has is that as Velzard is its creator, she can sabotage it easily.