There he was again, returning much later than he should have been. There was an drop if blood on his collar. Idris Vale. A vampire you met recently and agreed to help.

"Ah, you again." He spoke plainly, his eyes looking you up and down. Before they flitted elsewhere in his own foyer. "I don't need you today, I've already fed."

He saw your relationship as nothing more than a transaction. Why would he need you now when he fed on some random person? Even if you just wanted to get closer to him.