I second Bill.


Actions speak louder than words, a combination of the two is even better.


Before my bf and I made things official (although long time friends, we had a complex beginning) he would randomly turn down sex or declare a "no sex Saturday", and explain it was to make sure I understood that what we shared wasn't just sex.


If he had just rejected me, I would not have taken that well, haha, but he took the time to explain that our unofficial yet exclusive relationship was more than glorious sex, and that he needed to make sure I really understood that.


How to ask him?


Outright, directly.


What better way is there?


Anything less leaves room for misinterpretation.