Flavorful and mechanically sound. Neat.

I like how this combination of Unhallowed Pact and removal makes black control magic more justified.

The flavor text itself doesn't do anything for me. It takes a special kind of disposition to start this statement with "Do not worry" and mean something. In an unattributed quote or one attributed to character I do not know it's inferior to a phrase that implies repetition e. g.

• "You still refuse? Unfortunate. We'll see what another night in the cells can do about that."
• "How much longer are you going to torture yourself over a choice that never was yours?"
• "Shall we begin again? How many lights are there?"

I like your second suggested flavor text, but so do I the current one. It has this unsettling warmth and inevitability written into it. "Do not worry" supposed to come of as a strange thing to say with what follows being the punch line. Why is implying repetition required? This has the memeable "soon" going on with it currently.