After Ragnarok, Thor was able to choose which Asgardians to bring back from the dead with him. Loki managed to trick his brother into resurrecting him too however, but to punish the God of Thunder, he stole Lady Sif's (the love of Thor's life) body and kept this female appearance for a number of years. This was obviously quite an unusual decision, but proved to be a hit with fans. After once again dying though, Loki returned in the body of a male child and despite recently taking on an older form is still quite a bit more youthful than in the past. In fact, Marvel has actually made him the spitting image of Tom Hiddleston.
