User blog comment:B214/Volume 23 discussion blog/@comment-76.175.162.45-20170402000902/@comment-3965848-20170402010308

For the record, in fairness there's already a sister combo of Koneko and Kuroka in the harem and unlike Xenovia and Griselda, they're by blood.

Second, Angels are now able to mate with anyone without falling due to the interdimensional room.