Richter's hand is clean, now; it smells of lavender and citrus and nothing at all of skin and sweat and semen. But he can still feel Emil under it, can still hear him, and it hurts.
The ache is nothing physical; it's just this persistent, oppressive feeling eating away at the guilty arousal (it's a reflex, he tells himself, and nothing more. It's backed up by data and made worse by the microchip, and that's all). It's the way he keeps seeing Aster there, instead, keeps wondering if Aster would make the same helpless noises or if he would take control of something like that as he did with everything, would laugh breathlessly against Richter's skin, would…
But Richter cannot think these things, because Aster is dead. Aster is no more. He will never return; Richter has failed in his self-appointed task to restore the one person in the world who meant everything to him. As much as Richter likes Emil, finds himself grudgingly accepting Ratatosk, as well, now that he's taken responsibility, neither of them will be Aster. It's a cruel joke that they wear Aster's form so brazenly, that Richter can touch it as he will-- could have touched it more and Emil would have let him, because Emil would let Richter walk all over him in spiked boots, like a dog lying down for his master, and isn't that a guilty, horrifying thought that kills the last remnants of happiness-- but Aster himself will always remain untouchable and untouched.
Koli whines and licks at his fingers, and Richter twitches, pulls the offending hand up away from the dog's mouth. A lump of ice has settled in his chest, and he kneels down to snap the leash on before leaving the room. He can't stay here any longer.