The bases of dating
But this is a joke, and probably not intended to be analyzed too closely. Although this wasn't what "House" referred to, Urban Dictionary lists fifth base as anal sex.
One of the other answers has provided a nice link to the Wikipedia entry for baseball metaphors for sex.
Walk A walk is considered a sympathy base and is typically reserved for first base only.
Nov 20, 2011. Just for the record, I don't know if I've ever been completely taught what the “bases” are, but let's give it a shot. Figure if anything, we can sort it.… continue reading »
Jan 5, 2017. Somehow we as a nation managed to combine the least sexy and exciting sport with sexual stuff, that's why we must know what are the bases.… continue reading »
Aug 29, 2015. The four bases in a relationship, like in baseball, where the partners try to get home. Four bases of American dating * F1 - French Kissing First base is.… continue reading »