A Contest of Nisse and Release
The term Infernals is used to refer to the entirety of Exalted in service to the Yozis, regardless of their method of creation. It is important to note that while all Akuma are Infernal Exalts, not all Infernal Exalts are Akuma, like the Green Sun Princes.
There are two distinct groups of Infernals:
The Akuma, created through the unholy union of a willing Exalt (of any type) with a Demon. These beings have been around before the destruction of the Jade Prison but they are more akin to Demons than to regular Exalted.