Say you're a young, white, mid-20's bachelor who will soon have a PhD. You have a US citizenship that will let you go nearly anywhere on earth. You have no wife, no kids, no dog, and no mortgage. You can move anywhere and probably find employment. You want to have many women from which to choose, so it needs to be a sufficiently-large city. Learning a new language sounds fun, and is an option. Where would you go?