20. Professor X Was In Love With The Teenage Jean Grey
With a group of heroes as large as the X-Men all living under the same roof, it should come as no surprise to learn that a number of them have hooked up over the years. However, one of the strangest mutant romances came very early on in their history in the pages of X-Men #4. During a single panel, it was revealed that Professor Charles Xavier (who must have at least been in his 40s) desired the young Jean Grey, a girl who was likely no more than 15 or 16. This plot thread was thankfully left unresolved by Stan Lee and Jack Kirby, though Robert Kirkman offered an alternative take on this "romance" during his Ultimate X-Men run.
