The type of magic that healers use is weak, and is only useful for speeding up the body's natural healing process. Among other things, it can close wounds and stop blood flow, but it cannot remove or regenerate tissue any more than the body can do itself. Healing magic is unique to this group of angels, as they draw energy through their halos from Heaven itself. It is not possible to learn by any other means. Some demons are able to regenerate or heal themselves through magic, but the ability to heal another person has never been recorded in any magic user, demonic or otherwise.
Healer angels occupy many different types of jobs, such as field nurses, doctors and surgeons in established hospitals.