The core four of "The O.C." -- Ryan Atwood, Marissa Cooper, Summer Roberts, and Seth Cohen -- dated around quite a bit, especially when it came to dating each other. While they hooked up with some winners, they also exhibited some terrible taste in significant others.
There were too many fake miscarriages, girlfriends that turned out to be a sister (but not by blood, thank heavens), and accidental murders. At least we know Seth and Summer got their happy ending.
Without further ado, here is the ranking of everyone the core four ever had as a romantic interest.