User blog comment:B214/Season 3 confirmed!!!!!!/@comment-203.177.240.27-20150108232923/@comment-25935458-20150109001849

Not sure if I understand your questions correctly. But if season 3 follows the pattern of previous seasons then the ratings game from volume 5 will happen. So, yes Issei and Rias will be in a ratings game. As to "will they be together", not as lovers if that was your question.