User blog comment:B214/Volume 21 info & spoilers/@comment-27876048-20160320054403/@comment-213.120.234.146-20160320111856

From what I've read about arc 5 it will regain the more erotic aspects of the series that we had in arcs 1 to 3. From that we can assume that Issei's problem won't be permanent and he will get his perception back. I really hope that's the case B214, otherwise it pretty much kills the series, taking away from Issei what made him what he is. Kinda takes the soul out of the series, don't you think?