Quincy

The Quincy (滅却師 (クインシー), Kuinshī; lit. "Monk of Destruction") in modern terms, were Human mediums, having the ability to detect the existence of Hollows. It all started when they began training to confront Hollows in order to defeat them, the same as Shinigami do. Most of the Quincy were destroyed by the Shinigami over 200 years ago in order to prevent the destruction of the world. Quincy are the complete polar opposite of Shinigami.

Overview
Quincy are spiritually aware Humans able to absorb and manipulate Reishi into spiritual weapons. Spiritual Awareness: As a spiritual being, the Quincy is able to sense Hollows and other spiritual beings at a significant distance, and tell in what direction they are in. Quincy have an acute perception of Reiatsu.
 * Reishi Absorption: Although Shinigami and Quincy both use Reiryoku when fighting, they both have a completely opposite fighting style. Shinigami use the spiritual power created from their soul in conjunction with a Zanpakutō to fight against the Hollows. It can be said they fight using a power from within. On the contrary, a Quincy uses the Reishi in the atmosphere, and combines it with his/her Reiryoku to create weapons. They fight using a power from outside. They have an easier time collecting this energy in environments with higher concentrations of Reishi such as in Soul Society or Hueco Mundo. To a sufficiently powerful Quincy, there is no difference between Reishi and Reiryoku as a source of power.
 * Spirit Weapon: The weapon that Quincy create by gathering the Reishi in the air. The only limit to a Quincy's ability to create and fire arrows is their own stamina and ability to absorb ambient Reishi.

Gemischt and Echt Quincy
At some point within their history, the Quincy began to distinguish themselves based upon an individual's ancestry and adopted the practice of true-breeding. Those who were descended from a long line of only Quincy and so, were thought to have a pure heritage, came to be known as Echt (純血統 (エヒト), Ehito; Japanese for "Pure-Blooded", German for "Real") Quincy, while all others were instead referred to as Gemischt (混血統 (ゲミシュト), Gemishuto; Japanese for "Mixed-Blooded", German for "Mixed"). In order to preserve their pure lineage, many families conducted arranged marriages between their own children and only those belonging to other pure families.