User blog comment:TheBlueSlug/Ending/@comment-213.120.234.122-20141115123857/@comment-1359322-20141115125118

Actually Irina kissed Issei when he was sleeping, so Issei wasn't aware of the kiss. And the reason to Issei's girl phobia is Raynare, she toyed with Issei's feelings, killed him and when he became a Devil scorned Issei.

Also since this is a harem and Ishibumi wanting to end it on a happy note for all the girls, he'll make sure the girls end up together with Issei.