That's easy for me. Zero. I met Bob when I was 15 and only had one sorta sexual encounter before that. I say sorta because in our totally unexperienced young lives we kissed, he sucked and fondled my breasts, I fondled him but I didn't suck him. He tried to get his cock in me but ended up cumming on my leg. Bob and I had willpower and held off having sex..........................until our second date. We dated four years before we got married. So officially my official number of cocks sucked before marriage is one, Bobs.
Now since then............impossible to count and still adding more. 😊