User blog comment:B214/Question and Answers 3/@comment-3965848-20140620085601/@comment-3965848-20140620111411

Objects and abilities are used in different ways

Irina can only use it if Xenovia is there to lend it, like how Issei lends Ascalon to Xenovia.

Reverse can be used any time by the user without assistance of others, former defines something previously used and/or owned. Even if they choose not use it, it's not considered "former" unless it is removed from their capabilities.