Severus wasn't listening, and pointedly so after hearing the name Sirius. Instead, he concentrated on watching the tip of his finger disappear inside his lover's body while he slipped the forefinger of his other hand inside his mouth. Once it had been slicked with saliva, he switched fingers and worked it in.
"Fuck," Severus groaned. "We're going to need more than this, but I don't want to stop-- summon it for me."
Leaning in, he underscored the request with a sharp bite on the side of the other boy's neck.