On one of his journeys in Midgard when Loki was feeling especially bad, due to the mocking of the other gods in Asgard about his being the mother of a foal, the famous steed Sleipnir, whom Loki had given to Odin as a gift, he met the giant Angrboda. As she was praising his accomplishments, she was mocking him about his admiration of the gods. Do not listen to their mocking; they are descendants of giants just like me, and like you by the way!
That was just the kind of thing Loki wanted to hear. He fell in love with her and together they lived on a little island. Their first-born was a daughter, Hel. On one side of her face she had a beautiful baby face, on the other side she had...nothing. Not an eye, cheek nor ear, nothing. If you stared in it long enough it was as if you were staring into the depth of the ginnungagap. Only Angrboda wasn't alarmed by the whole thing. Hel grew up to be a silent little girl that always seemed to walk with her head down. Loki forgot his worries about her when a second child was born. A son this time, Fenrir, he wasn't human nor was he a god. He was a big horrible wolf. In one weeks time he grew half as big as his mother. He could easily bite through the thickest bones and branches. Loki tried to escape the island. On the beach he thought about his daughter and went back to get her. In the hallway he ran into Angrboda. She reminded him of the mocking of the gods. Her eyes lit up and she pulled Loki near. Loki stayed, and yet another child was born. A snake so gigantic, so horrible and so poisonous Nidhögg the dragon that was chewing away at the roots of the life tree Yggdrasil was nothing compared to it. This was the snake Jörgumangandr. Angrboda's laughter and Loki's scream of horror could be heard throughout Midgard.
On hearing that sound Odin came riding his 8-legged steed trough the sky. With his spear Gleipnir Odin chased the serpent into the depths of the ocean, where he was to stay until the end of days. Jörgumangandr was so long he could circle the world and bite the tip of his own tail. Angrboda's last words to Loki as she fled to Jotunheim, the realm of the giants were: " follow me, I'm a giant you're the son of a giant, your place is with us. Don't tell me your not proud of the devastating forces of your children." This reminded Loki of how Freya had encouraged him to feel proud for his son Sleipnir. "follow me" said Angrboda one last time. But Loki went home with Odin to Asgard. He took his son and daughter with him.