Kono Ai wa Itan.: Belial Bunsho  

The Heresy of Love: Belial Papers, この愛は、異端。-ベリアル文書-, Kono Ai wa, Itan.: Belial Bunsho

The narrative is about a sensual tale involving the devil and a young woman named Yoshino, who was not included in the main story at age 18. At her eighteenth birthday, her contract with the devil Belial will undergo an alteration. A kiss that involves entangling one's tongue will be considered as part of the deal. Additionally, there is a record kept by Belial detailing how things shifted from being managed by parents to adults of both genders as seen from his perspective when Yoshino turned 18.