By nature, Kryptonians are very sexual creatures; sex for them is a major means of life, to create, to proclaim love, to pass the time; to a much more liberal view than any average Earthling would view it. Cut to the last living Kryptonian, raised as human on a planet not quite his own; he finds his body going through odd changes ever since he met Batman. Clark never met such a dominant for in his life before that fateful night, unknown to him, his body and very soul has accepted Bruce Wayne as their chosen mate. Clark, desperate to keep his feelings to himself, further solidifies his relationship to Lois by proposing. Cut to Bruce, who has found himself oddly drawn to Clark ever since he took the time to get to know him; with the pending engagement has decided it's time to take who he knows is his before it's too late, come hell or high water.