Having a big wang has ZERO to do with pulling ass.
It's about one ore more of the following...
Having money. You already know this, so no discussion necessary.
Having an air of confidence...this can include a lot of things, but having a personality that women are attracted to means a lot. Being funny, standing out in the crowd of guys with a unique and distinctive persona, doing things that catch their eye...this is a very hard thing to describe, but some guys just have an ability to attract women with the way that they act around other people
Do something "cool"....again, hard to quantify...but musicians have this. I swear, I knew a guy in college who sang in a band...other than that, this guy had nothing going for him. He was losing his hair at 21, he had bad skin, no money, lived in a shitbox apartment, but he pulled hot ass like it was nobody's business.
That's all I have time for now, but that's a start. #2 is most important.