Aiwass is a higher dimensional super-being summoned by Aleister Crowley. An entity ranked above angels, Aiwass was Aleister Crowley's former mentor, and the true author of the "Book of Law." Aiwass also refers itself as "DRAGON," saying it's more accurate as being called an "extraterrestrial intelligent being," "holy guardian angel," or "the true master of the secrets that shaped modern western magicks".
Aiwass' gender is unknown, though Aiwass has been described as having feminine slim body and long hair.
As opposed to Aleister Crowley, who judges things on their efficiency, Aiwass judges things on whether it has value or not. It seems disinterested in the affairs of the world, though showing interest in both Accelerator's and Kakine's abilities. It also knows of Crowley's true intentions, being his former mentor. It was also the one who prompted Hyouka to go to Russia to participate in the war; this decision may be against Crowley's best interests, if so it implies that Aiwass has plans of its own.
Due to its own disinterest in most things, Aiwass offered Accelerator to let him destroy its physical form, saying it'll buy him time to save Last Order, and that it doesn't matter if it vanishes, as it can always return in 10,000 or even 100,000 years later. In addition, it also doesn't care about Aleister's threats about losing its status as above mortals forever, saying that it never asked for its powers in the first place and it would not matter either way.