User blog comment:Mnzombie/Issei's Peerage/@comment-24017079-20131006010020/@comment-5185939-20131023082048

She doesn't 'want' to fall, but I think it was stated at one time she 'will' if he really wants her to.

Basicaly, she wants to be both an Angel, and with Issei, but if she had to choose, she'd go with Issei.