User blog comment:B214/High School DxD EX/@comment-201.239.133.207-20170104020556/@comment-31137559-20170209170114

And Ex is pureblood. Halfblood refers to a devil and another species. Issei is a devil and has been accepted into their society. And he is basically engaged to Rias although he hasn't proposed or anything, people acknowledge them as basically being married. And if it was such a problem, it would have been addressed. It said Rias stepped down from her position as family head. And Issei is a reincarnated devil. Devil+Devil=Pureblood devil. Issei is acknowledged as a devil by the other devils regardless of his origins. Think about it like this. Harry Potter is considered a pureblood wizard. And Harry's mother is Muggle-born like Hermione. For Ex it would be the same. Else there would be no point in the reincarnated devil system. Halfblood refers to when devils have children with other species. Lilitifa Vepar is a mermaid, but also a devil. Liban Crocell(Sairaorg's Knight) is a devil, yet half-human and has a Sacred Gear. Same with Sairaorg's bishop, Misteeta Sabnock. And Vali is half-blood because his mother is human and he was born with Divine Dividing because of his human roots. Both of Ex's parents are devils which makes him a pureblood devil. It's just that a lot of devils believe that pureblood high-class devils have to marry pureblood high-class devils.