He doesn't believe it at first. Can't. Not of the headmaster, who drew him from a dark ocean the first time, gave him a stable shore after he shipwrecked his own and Lily's lives.
It’s a lie, Severus thinks. The Dark Lord will say anything to keep a useful spy at his command. The boy is the reason Dumbledore did not cast him back, after all. Even if he doesn’t care for Severus, he loves the boy.
A few careful inquiries prove him wrong.
He agrees to a second conversation, another grant of clemency.
Without the headmaster, he is adrift.
Twice he's walked away a traitor and lived. Twice the Dark Lord has offered him forgiveness, if Severus will give his.
This is unheard of.
He wants Lily's son to live. Is it too hard to imagine he wants Severus also? Even if—it must be—only to protect the boy.
Though there are other ways to do that, Severus reflects.
A third meeting, then. He gave Lily three chances; Severus can give him three in return.
And what other way forward does he have, really? He cannot go on alone—this he well knows. He has always needed direction.
Little new is said this time. There’s little new to say. The Dark Lord knows what Severus wants. What he needs.
One pale hand reaches out.
Softly, almost a plea: "Come back to me, Severus."
Something inside Severus breaks, and he slips to his knees there on the floor between their chairs, trembling.
He glances up. Glad red eyes meet his.
He bows again, does not see the coldness come into those eyes as Voldemort bends to kiss his forehead, hears only the warmth of the voice that speaks in his ear.
"My prodigal son."
He is home.