User blog comment:Crimson and Darkness/Volume 24 discussion blog/@comment-73.57.25.92-20171117173758/@comment-27083298-20171117174834

Mating with any other species would make their children half-breeds.

Like Shirayuki and Kurobara for example, their mothers Koneko and Kuroka are pure Nekomata and their father Issei is a Humanoid Dragon.