User blog comment:B214/Volume 23 discussion blog/@comment-172.56.17.58-20170417051436/@comment-31137559-20170417120718

Well Rias does have her family wealth at her disposal which is going to be hers when she becomes the heir. But Issei will become Issei Gremory when he marries Rias. And then there's the immense amount of money flowing into his account from the Oppai Dragon franchise and his devil's job. And then if he gets up there in the Rating Games, his wealth will skyrocket.