This is the first time in a while I've actually been interested in the backstory of one of the contestants. Helps that it's tied in to the main plotline with Brunhilde, but it's nice to be invested in this series for a change!
Loki is basically a child. He's acting like "if i can't have it, no one will". Also, his mentality of thinking that, if Sieg was out of the picture, she would smile towards him, and only him, is also a child-like mentality.