Rinku Clan

The Rinku clan is a mysterious clan that resides in the leaf village. The members of this clan are all vampires. Many vampires of this clan's have Yin-Yang release.

Vampirism
The reason behind Rinku's clan members being vampires is a mysterious one. According to the rumors circulating Konoha, the first "vampire" was just an average person who was immune to blood born diseases. That "vampire" later married a a women who had supernatural strength due to her being the  jinchuriki for Son Goku. The two unusual traits mixed and their son became the first "true vampire." As well as the first vampire  jinchuriki. That explanation however doesn't explain Tsuki's unusual transformation.

The genes of the Rinku clan are so strong that any Kekkei Genkai that a Rinku member may have gotten due to their other parent would be eliminated. Their is one exception to this rule. That exception is Taiga Rinku.

Legend of the vampire goddess
This legend is passed down from generation to genrationn within the Rinku clan. It is forbidden among the Rinku to speak to it to an outsider. The legend says that long ago before even Rikudo. There lived a women who lived outside of civilization. Depections of this women show her as a beautiful women with snow white hair, glowing red eyes, and she had much chakra that she had to continually release it.