User blog comment:Jopjopjop/Volume 18 Spoilers/@comment-173.71.153.83-20150210171741/@comment-98.227.238.52-20150226030845

There is really no such thing as a pure race anymore. Or in their case a pure blooded clan. Rias' mother wasn't a part of the Gremory family she was from the Bael clan. Zekrum's clan and she married into the Gremory family and had children. Sirzechs and Rias have traits of both the Bael and the Gremory. They aren't more of one than the other.

Frankly, I don'[t understand why everyone keeps saying their pure bloods. Yeah, they maybe full devils. but they aren't pure bloods. They are the off springs of two different families.