Magic Channellers are a relatively minor CLEA designation on account that not many have been recorded due to the fact that most are unaware they have the ability. Unlike other Magic users, Magic Channellers have no offensive capabilities.
What these people do is channel dark or light magic (but never both). The magic merely acts as protection from its counterpart. Channelled dark magic protects the bearer from light magic and vice versa. More often than not, this ability is latent and the bearer unaware that they are doing it. Whilst purely a defensive ability if a Channeller is aware of their gift it can be used as a weapon by acting as a “sink” against powerful offensive magic, reducing or even nullifying its effects.
Dark magic channellers are usually distant relatives of those touched by dark magic, such as half demons, witches etc. Followers of dark religions can also inadvertently channel magic. Those who choose to serve Demons in the mortal realm but do not practise magic directly can often channel magic, simply by having their soul linked to a source of dark magic.
Light magic channellers can be related to light magic users but most simply get it through following religions with links to the Light Realm. For this reason they are sometimes called pure hearts and are often protected by Angels. Many Demons avoid tempting fate by corrupting a pure heart out of fear of what might happen to them.