like yes, fionn does genuinely love sex for many reasons, including that for a long time it was the only way he could feel wanted, however briefly that was for
but really what he craves is the intimacy, and that's something he doesn't get from casual hookups. he wants the being known, the being seen, being understood, as terrifying as all of those also are, and wants them in reverse too. he wants to understand and be able to read someone's body & reactions, he wants deep eye contact and silent communication. he wants physical intimacy that isn't just sex: long makeouts and snuggles on the sofa and and feet in laps and slightly possessive hands in company. he wants to bathe together and (literally) sleep together and wake up together and eat breakfast together. he wants to feel safe talking about things he never talks about. and yeah, sex too, but it's just one part of the whole