User blog comment:B214/Talk About What You Want! 2/@comment-108.27.243.235-20140707032420/@comment-24866657-20140707104924

Of course it took time to make Rias realize if she truly loves Issei she would support his harem dream, and, well in a view having "sisters" to do things together like a family is better than doing it all alone, since DxD isn't serious to begin with we can take it easy.

When I mention mistresses it's not necessary for one to marry to be called mistresses, I think I wasn't clear.

Anyway what I want to point out is the case between Issei and Raiser is different.