If I had to guess, it's probably along the lines of he understands that people in love have sex; full stop. No other variables. Some people (including me) are just wired that way, in that I can only have sex with someone I have a deep romantic connection with and no desire otherwise. I think he's just realizing that while he thought he was that way, that's not entirely true anymore.

i feel like blessed having 2 chapters in a row in 2 days also what does he mean by sex equals love premise thingy, i canβt understand that part