i think it depends on luck....5 years ago I got to know 3 girls from dating site within a week, and bed all of them during the first meet up.
in that year, I ever had like 6 FBs at the SAME time, i basically had sex every night, some times even twice a day with different girls...until I have to do it outdoor or in car to save hotel $$$
today, I have no more lady luck and have 0 FB after searching for years