1. Steve/Loki—They're secretly married and during an interview, Steve's wearing a wedding ring, so they go into damage control. I think they end up bringing Loki out and he's been helping the Avengers, so they try to gain some support. **This is actually the same as below, or at least a part of the same series, making it Tony/Loki: Nothing Will Cage Me Any More by FujiDawn http://archiveofourown.org/works/992044**
2. Either a Steve/Loki or a Tony/Loki where Loki slowly works his way into their lives. I remember a Christmas scene where each of the Avengers receives a very thoughtful gift from Loki. I think Steve or Tony gets a healing stone that will heal anything and eventually saves their life—maybe Tony, something to do with his heart/arc reactor. **Just found it: Nothing Will Cage Me Any More by FujiDawn http://archiveofourown.org/works/992044. The summary was "It had taken one second of distraction for Loki to escape." But it's basically Loki escapes to Earth, sets him/her self up with a few identities and keeps running into the Avengers, particularly Tony Stark.**
3. Tony/Loki where they met when Tony was young and stayed friends throughout. I think Tony gets invited to visit Asgard. I don't think that any of the movie plots came into play. I'm pretty sure it was a series on AO3. **I'd gotten this mixed up a bit. It was actually young Natasha and Tony. The story is THE LITTLEST VALKYRIE by Bluetoast http://archiveofourown.org/works/1513667. Loki adopts a young Natasha after discovering the Red Room. Natasha and Tony meet when he is 5 and Loki is working with Howard Stark. She asks every year on her birthday that Tony be allowed to visit, but Odin refuses. It's incomplete, last updated in July 2016. Fingers crossed that it continues. It's very well-written and even though it's a hugely different timeline, the events of the Avengers movie happen in some way or another.**
4. Loki is de-aged and Thor brings him to Avengers' Tower. I remember Frigga comes with chests of clothing for young Loki, who prefers Asgardian clothing, and gold for Tony for housing them. I think it was a WIP. **Just remembered! Redemption (Start It Over Again) by hotchoco195 http://archiveofourown.org/works/1085425 **
Thanks in advance!