Highschooler Motoki meets Shidou and will learn that he is not as normal as he thinks. He (or more particularly his heart) is a source of power and can extend lifespan. He will soon become the target of some semi-immortals, including Shidou, but both Shidou and Motoki will fall in love with each other.
Shidou will have to fight against his own desire to eat Motoki's heart and protect him from the other hunters.
==I did not expect this kind of storyline from Yamakami Riyu, and it was very well done. I particularly like Shidou's character and his struggle not to eat the offering's heart, even knowing that his life will be put on the line. The power of love!
Taiyou no Romance*