User blog comment:B214/Volume 1 - 15 Discussion/@comment-24230475-20131130230842/@comment-1359322-20131207060909

Well all being said yes Rias does have a slight inferiority complex over he brother but that is only because Rias was only made the Gremory Clan heir after Sirzechs lost his right to inherit it, so it was actually Rias that placed the unnecessary burden on herself to try live up to the Gremory Clan name like Sirzechs would've done if he was head. But it didn't really affect their relationship since really do love each other.