User blog comment:B214/Question and Answers 2/@comment-4547267-20140227145305/@comment-1359322-20140227145634

That's cause Akeno only pretends to be lustful but in reality she has no experience in such things and is actually really shy about such things much like Rias is. They just don't try to outright display it but they are actually very pure in that field, otherwise they won't feel jealousy and such.