Ryo Asuka arranged the Sabbath when he invited a large group of hippies, perverts, and general social drop out to a party at his home. Later he brings his friend Akira Fudo to the Sabbath with the intention for them to both become Devilmen. Needing only to spill blood Ryo sets about killing his guests, until they start to fight back and both Ryo and Akira begin to get beaten themselves.
Luckily for them however the demons begin to fuse with the guests starting with the female demoness Welvath. Slowly more guests are transformed until a large majority have turned. After feeling little to no effect, Akira fuses with the mighty demon Amon. However his pure heart successfully dominates that of Amon's and he becomes the Devilman.
Amon: The Darkside of DevilmanEdit
In the Amon manga, the insane psychopathic Devilman Cadney is seen as a guest at the Sabbath. But instead of getting killed or fusing with a demon, he becomes a Devilman similar to Akira, however his twisted mind convinces him that he is the only one true Devilman.