Chiaki Hayasaka (Baal Avatar) Profile
A friend and class-mate of the protagonist, Chiak comes from a high-class family; she tends to see lowly of other people (including Isamu). She managed to survive the Conception since she was inside the Hospital before it occurred; for some time she wandered alone the new Tokyo, scared and without hopes of finding other humans, until she meet again with the protagonist (now known as the "Demi-Fiend"), this gave her higher hopes and will to find out what had happened to the world.
Later, she understood the situation, in order to make a new world the old one had to be "destroyed", and only those who had enough power (or "Magatsuhi") would be able to make the new world as they wanted. Chiaki then decided to obtain power and make her ideal world, an elitist world, a world were only the strong and the beautiful could live on, were power was everything... the world of "Yosuga".
At first she tried to do it alone (since she wanted to prove she alone was strong enough), by obtaining the "" but the manikin obtained it first and left Chiaki with deadly wounds. Weak and desperate, she looked for power and sought the power of Gozutenno (who was thought dead, but his spirit and power remained), this last one saw the strong desire for power of Chiaki and her ideal world and accepted to lend her his power. Thanks to that, Chiaki became a powerful and "beautiful" demon and took over command of the Mantra as well as various demons from the "Seraph" and "Divine" clans.
In order to make a world, one not only needs a "Reason" and "Magatsuhi", but also the "guidance" of one of the supreme Gods. In order to summon it a large amount of Magutsuchi is needed. Chiaki invaded Asakusa and killed nearly every Manikin of the city for she knew a large amount of Magatsuhi was held in Mifunashiro (and also because she found the idea of the Manikin, previously slaves of the Mantra, trying to conceive a Reason and make their world, a sick joke). The Demi-Fiend managed to arrive in the moment Futomimi (leader of the Manikins) and Chiaki were about to battle. Depending on his "beliefs" he either helps Futomimi and battles the Seraphs Raphael, Uriel and Gabriel, or agrees with Chiaki's Reason and he himself kills Futomimi; regardless of the choice, Chiaki manages to collect enough Magatsuhi and summons her god: Baal Avatar, who then disappears.
Later, the Tower of Kagutsuchi appears and all of the major Leaders for each Reason climb it in order to meet Kagutsuchi and make their world. Chiaki (now inside of Baal Avatar) is the first one to arrive and the last one the Demi-Fiend has to deal with (unless he is following the same Reason, in that case they don't battle). In the case of them battling, both agree that while they used to be friends and that she respects his strength, their Reasons are different and only one can be superior. In respect of them both once being friends, they battle using their full power. In the end, Chiaki is defeated and Baal destroyed. Before dying, she wonders why if the Demi-Fiend had so much power he didn't agreed with the Reason of Yosuga.
If the Demi-Fiend was with Yosuga, he would instead battle Kagutsuchi in order to prove his Reason to be the strongest. After succeeding, the world of Yosuga is created. Chiaki appears (back on her human form) and thanks him for helping her. What happens after, one can only wonder.
Finally, if the Demi-Fiend didn't ally himself with any Reason and remained Neutral (neither Demon nor follower of the Light) the world is restored to it's original form before the Conception. Everything is restored and even his friends brought back to life. None remembers what happened, except him and Yuko (Teacher of him and his friends, also known as the "Maiden"), who thanks him for freeing the world of the cycle and giving each one their own freedom to follow their lives any way they want.
