Hannibal's love for Will is associated with hunger, being nourished at the sight of him. He can't ever consume Will and literally be nourished by him because then he'd be gone for good, so his mere presence has to satisfy his hunger instead. Sharing space and drinking in the same air. Devouring every detail to savor and digest, basking in the warmth of Will's understanding wrapped around him.
Will's is pain, an ache. "Do you ache for him" - "Do you hurt for him." Hannibal's way of loving can scar, yet Will continues coming back to him despite his suffering. Despite knowing there's the possibility of pain, knowing what Hannibal's capable of. He endures and embraces it. The love is painful, and the pain is given lovingly. Will's figurative wounds don't close, they stay open on the inside - the places where Hannibal cut through his shell to slip his hands in and guide him out.
