Creed (DxD)

Zayyn Illya Kovalenko was just an ordinary boy, an orphan from the outskirts of Romania. Until one meeting changed everything. A simple encounter with a certain silver-haired young man. That night, as his world collapsed, a single resolve was born. A creed that would lead him down a path of grief, darkness, and blood. A creed to kill every single Devil. — Description from novelcodex.org