User blog comment:B214/High School DxD EX/@comment-50.139.232.230-20151201224740/@comment-49.177.95.187-20151202010205

Millicas oldest kid would be next head but only if a pure blood devil under current devil rules, but that rule may change as well if they go by power than pure blood lines, eg maybe Issei being a devil king in the future may help change things on that part.

Also if they do allow half bloods to carry on as clan leaders you would maybe expect some old folded houses to maybe come back as there seems to be a few half bloods with power that could take over as the new heads.