I like that angle you suggested. Maybe he is skilled with the use of his 'props' if you could call them that. Blindfolds, rope, handcuffs, cream, strawberries, ice, scarves, that sort of thing. He is game for whatever his client wants. He caters to their desires. Maybe his reputation can involve a combination of these things. Sophia's friends or acquaintances could tell her about how skilfully he catered to their fetishes/.