User blog comment:B214/Volume 23 discussion blog/@comment-172.56.17.58-20170417051436/@comment-31137559-20170418020856

Volume 13, Extra Life, Quote from Issei:

"A crimson-haired boy with a bag on his back came to visit! Millicas Gremory-sama! The only son of the Maou Sirzechs-sama and his wife, who is the strongest [Queen], Grayfia-san! For the House of Gremory, he is the next heir after Rias. A real Prince! An Ouji-sama!"

Why would he be considered the next heir after Rias if he is the intended heir? Sirzechs was the intended heir but he became Lucifer and lost his right to inherit the household. Rias is most likely going to become the head of the Gremory household after she graduates from college. It was a matter of who was born first not being the son of the intended heir. Now when Rias becomes head Millicas would become the heir because of there being no other Gremory until Rias and Issei have a child. That's like saying if Sairaorg becomes Lucifer and Magdaran becomes head and they both have children, that Sairaorg's child would be the heir no matter if Magdaran's child was born first just because the proper heir-line was Sairaorg.

Now Rias is 17. Millicas is somewhere around 10 years old I would say. That makes him less than 10 years younger than Rias. And Rias will most likely become head when she graduates from college. Millicas would be a teenager by then. Rias would barely have any time to be the heir.

Now I get your point, B214. But Sirzechs forfeited his right to become head of Gremory when he became Lucifer. Thus he never became head. Now if he was head, it wouldn't matter that Millicas was younger than Rias. Millicas would be the son of the head. If he was born before Rias, he would be the heir instead of being the next heir after Rias. Rias is still undeniably the heir. If Millicas was the heir then Ishibumi would have mentioned it. And if Rias was a placeholder then she wouldn't be the heir.

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