When two demons are too dissimilar to reproduce normally (such as Varin and Krog), the only way they can have a child is to create one by fusing their magical essences, sacrificing a part of their powers in the process. The child will probably be a messed up abomination, but will most resemble whichever of its parents laid its egg.

Examples: Murgatranthes (Ontos/agrilthean fusion)

Humans who summon demons for fun and profit. Many summoners learn to conjure magic of their own, but they will never be as adept at it as a demon, who are naturally magical creatures.

Not infernal. Primals and fae are unfernal.

Elementally neutral magic.