Sylph

Sylphs are a low to mid-level class of Demon that possess the air and are related to the King of Spirits, Azazel.

Overview
Sylphs are demons of air. Appearing as small females with wing like arms, they can be invoked by producing elements they like, such as fire or water.

While normally Sylphs, like Naiads and other elementals, do not possess fatal verses, Lewin Light somehow developed one consisting of a single word 'Mortem', the Latin word meaning 'death'.

Powers and Abilities
Air Manipulation: Syplhs possess the ability to manipulate air currents, able to replace the stagnant air in a room with fresh, clean air in a matter of moments.

Cutting: While not entirely clear how, Sylphs can cut people by passing them quickly. While painful, it does not seem to cause much damage over all, appearing akin to a paper cut or similar injury.
 * Circular Saw (サーキュラソー): A sylph manifests above the hand of its summoner, its lower half spinning rapidly to create a disc-like blade.

Tracking: Sylphs have been shown to be used in techniques for tracking targets.
 * Sylph Bell (の鐘): A sylph is used to place a mark on a target, allowing their summoner to know their rough location at all times.

Trivia

 * Sylphs are an Air Elemental in Alchemy first written about by Philippus Aureolus Theophrastus Bombastus von Hohenheim.