Multi-chapter story on ff.net
It was jotun Loki sneaking into Asgard in disguise and meeting Thor. Here are a few scenes I remember:
- Loki meets Thor and the warriors 3 in a bar(?) and Fandral flirts with him. Then Thor talks to Loki and Fandral says something along the lines of "He always takes the hot ones"
- Loki being sympathetic towards jotuns when the group talks about them, leading to Thor thinking that Loki is in love with a jotun and wanting to rescue him from the monster
- Loki doesn't know how to ride, so when the group takes a trip Loki rides on Thors horse. Someone (I think Tyr) asks since when they take whores with them on trips
- Loki always sneaks back to Jotunheim
Pretty sure it was a wip