User blog comment:B214/Question and Answers 6/@comment-86.153.130.40-20160802001312/@comment-86.153.130.40-20160802035507

That explains somethings but it doesn't explain why Issei is the only one who has trouble with his devil wings because sure they must be and physical trait of a devil becuase other devils how have problems with their magic don't say they have a problem with their wings