Re: [Reaction.]
[Billy isn't cursed with supernatural hearing, but he does rely on Atticus' setup for running water, and it's with a deliberate visit to fill his kettle that he leaves the trail of his scent (homemade candle wax and the lingering stink of patchouli from Marta's sachet that he hasn't yet managed to wash off, despite several showers) in the man's living space for whenever he comes around. It's not a judgemental sort of smell, cross his heart. Instead he leaves a handwritten note, scrawled on a notepad and left on an end-table in an attempt at not being overly intrusive:]
It's for protection. To ward off magical attack, and dispel melancholia exorcise negative energies.