Loki Kermit

Loki Kermit is a Pureblood wizard who is a loyal Death Eater to Voldemort.

Harry's Destiny
Loki accompanies his master, Lord Voldemort, on Halloween as they wreak havoc and destruction in London. He then leaves a while before Wormtail meets up with the Dark Lord. Loki isn't sent to Azkaban, and states that he was under a mind-control curse.

Goblet
Loki is seen with his twin, Larry, at the Quidditch World Cup. He entertains people by juggling frogs. When the Death Eaters attack, Loki abandons his frogs and flees, though he is seen running around various times. When Lord Voldemort is resurrected, however, he is summoned. Loki, knowing not to defy his old master, came as a Death Eater and attacked Harry Potter and Cedric Diggory. Loki is one of the surviving Death Eaters.