Loki has a twin sister, no one knows. Thor, Odin and Loki all know of lokis twin sister. Loki is the god of mischief, Jaz is the goddess of dark creatures. They are 'different', but not really.

Loki is more cold and 'evil', while Jaz is more calm and happy. But I'm reality, they are both the same, misunderstood and forced to be 'evil'. They were both pushed away and abused by Odin, Thor was favored by odin.

Loki is an Avenger and Jaz decides to come as well, they look identical.