Loki is a member of the Fairy Tail guild. He is very flirtatious with attractive women, being top ranked "Mage you want to have as your boyfriend". He attempts to flirt with Lucy but after finding out that she's a Stellar Spirit mage, he quickly stops his advances. Mirajane said that something must have happened to him with a similar female Stellar Spirit mage. She also mentioned that Loke once tried to flirt with Erza, but nearly got himself killed because of it. His weapon is a magical ring and is skilled in "hand-to-hand" combat.
He seems to have an interest in Lucy, despite his fear and is the one who searched for Lucy's lost keys and subsequently saves Lucy from bandits.
After his sudden departure from Fairy Tail, Lucy discovers that Loki is a Stellar Spirit, Leo the Lion. His master was the famous Karen Lilica, who was a member of Blue Pegasus. Since her death three years ago, he has remained in the human world, unable to return to the Spirit World because he was exiled for killing his own summoner. He reveals that prolonged stay by a Stellar Spirit in the human world leads to imminent death.
Although he says he killed Karen, he did not kill her himself. Karen was abusive, vain, and arrogant towards her other Zodiac Stellar Spirit, the timid and kind Aries. One day she was about to punish Aries by forcing her to remain in the Real World for seven straight days, something that would probably kill her. Sick of Karen's apparently frequent tantrums, Loki summoned himself in Aries' place and refused to go back to the Spirit World until Karen broke both their pacts and left her house. However, Karen died on a mission before she could release them. This was due to the fact that she couldn't summon any other spirits while he was already summoned and thus he blamed himself for her death.
Although Loki had given up hope and was more than willing to die, Lucy managed to convince the Stellar Spirit King to revoke his exile. Loki is now one of Lucy's Stellar Spirits. He promised to be Lucy's backbone, and returned to the spirit world to recover. With him, Lucy now has half of the Gold keys.
After recovering, Loki is seen flirting with Lucy and being friendly with everyone. He declared that he has abandoned his old ways, flirting with only Lucy now. He has also self-proclaimed himself to be Lucy's knight in shining armor.
Fairy Tail follows the story of Lucy Heartfilia who joins a wizard guild called Fairy Tail. Below are the 20 most tear-jerking moments from Fairy Tail. Be careful as this list may contain SPOILERS, and make sure that you get your tissues ready before scrolling down!