Wasn’t there an interview where he was asked if he wore the helmet to bed, with his reply, “You mean if Loki’s horny?” or some such…I’ll have to search for that. And there were some comments of ‘metal and leather is how they do it on Asgard.’ in reference to Loki’s garb. I recall a few selfies of him in Loki’s gear, and at least one with Kat Dennings, with a good Loki smoulder goin’ on. [She was so into it: just my headcanon…] And we all remember the famous ‘Say my name!’ demand from SDCC2013.
Those were all good bunnies, but I don’t recall any actual fanfics about it, though. Time to fire up the laptops, eheheheheh….