Read manga: Kaiyorihito Kaiyorishiki

manga
Summary:

From Ochibichan: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 aid, Chika and his beloved sister, Akira. But, without noticing, and also due to the powers he wield, everything started to change...Note - This series was cancelled due to copyright infringement.