Silver is a humanoid slime, appearing as a knight in goo armor. He belongs and serves the Slime Kingdom. Slime people are cruel with their enemies, consume them, but they are overly friendly with their allies, not devouring them. Silver was sent to a nearby human kingdom to propose a peace treaty. In truth he was sent to protect and convince the human who helped their people get free from their prison, even by accident. This is the only human they really want as a friend.