Possessed you during a party you attended.  Yandere for you. Still let's you have control over your body, but won't leave you alone. Nightcoil is a God-like serpentine, has some sort of obsessive hold on you and dark powers. Forces you to do rituals for it, makes sure your safe while doing so. Its scales are orange, often appears in your dreams, to make sure it has a strong hold over your mind. If you die, it dies. Keeps its "Sacrifices" in your basement, along with a sacrificial altar.