Season 1
Humans and demons are two sides of the same coin, as are Assiah and Gehenna, their respective worlds. The only way to travel between the realms is by the means of possession, like in ghost stories. However, Satan, the ruler of Gehenna, cannot find a suitable host to possess and therefore, remains imprisoned in his world. In a desperate attempt to conquer Assiah, he sends his son instead, intending for him to eventually grow into a vessel capable of possession by the demon king. Ao no Exorcist follows Rin Okumura who appears to be an ordinary, somewhat troublesome teenager—that is until one day he is ambushed by demons. His world turns upside down when he discovers that he is in fact the very son of Satan and that his demon father wishes for him to return so they can conquer Assiah together. Not wanting to join the king of Gehenna, Rin decides to begin training to become an exorcist so that he can fight to defend Assiah alongside his brother Yukio.
Episodes
1 The Devil Resides in Human Souls Apr 17, 2011 
2 Gehenna Gate Apr 24, 2011 
3 Brothers May 1, 2011 
4 Garden of Amahara May 8, 2011 
5 A Boy From the Cursed Temple May 15, 2011 
6 The Phantom Chef May 22, 2011 
7 Flock of Plovers May 29, 2011 
8 Now a Certain Man was Sick Jun 5, 2011 
9 Memories Jun 12, 2011 
10 Black Cat Jun 19, 2011 
11 Demon of the Deep Seas Jun 26, 2011 
12 A Game of Tag Jul 3, 2011 
13 Proof Jul 10, 2011 
14 A Fun Camping Trip Jul 17, 2011 
15 An Act of Kindness Jul 24, 2011 
16 The Wager Jul 31, 2011 
17 Temptation Aug 7, 2011 
18 Gale Aug 14, 2011 
19 An Ordinary Day Aug 21, 2011 
20 Mask Aug 28, 2011 
21 Secret Garden Sep 4, 2011 
22 Demon Hunting Sep 11, 2011 
23 Truth Sep 18, 2011 
24 Satan's Spawn Sep 25, 2011 
25 Stop, Time! Oct 2, 2011