Kaiyorihito Kaiyorishiki

Aritsune is the head of the clan which wields the power of “Kaiyori”. As long as one can obtain the “Aya” which the clan head holds, no matter who, he will gain magnificent powers…
He lives a normal school life with his trusted aide, Chika and his beloved sister, Akira. But, without noticing, and also due to the powers he wields, everything started changing…

Note: This series was axed after 2 volumes due to copyright infringement by the author.