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.
(Source: Wikipedia)