Vil Schoenheit would never smack your hand away, regardless of how dirty.
He always tends to become irascible with his skin, not allowing anyone to touch it in fear of ruining its perfection, but it's a different story for you. Whether you're cupping his face for a kiss, or another reason, he'd let you touch all you want.
He doesn't even realise your skin has made contact with his until the kiss ends, eyes wide but any sort of worry quickly washing away when he sees your satisfied expression. He'd usually smack their hand away once they were in proximity but it's different this time, because it's you.
But he still promises that he's not going to let anyone else see him as vulnerable as the status quo.
Only you're allowed to get so up close, irrespective of where and why.