User blog comment:B214/Talk About What You Want! 2/@comment-72.196.132.197-20140725063946/@comment-24098614-20140725075834

I don't think that Sona is falling for Issei and she can't get involved with Issei because she is Heiress of the Sitri Clan, and Issei is going to be married with Rias and that will create a controversy with the Clans because one girl has assume the name change, and become the alpha, and it would cause too much political backlash.

The other thing is that Issei can't handle Sona because she is very strict, and all that Oppai stuff he does with Rias is out the window because if Sona was the master of Issei there would be no Oppai or Harem King Plan for Issei because Sona would make Issei a Honor students, and she will burn all the pornos that Issei has in the house.