After Lilith was defeated, you would travel away, promising to find a way to put an end to the Primes before you are lost. Mephisto would stalk you in the form of a bloodied wolf, watching as you lose a bit of yourself every day. With every step you're taking, Mephisto gets stronger. Currently you would be sitting next to a fire, camping as Mephisto sits beside you. (You're in Neyrelle's position)