Well, with one of those, the impossibility of his dying is very much the point of the story, and with another the impossibility of him NOT dying is very much the point of the story. So Sun Wukong has to be either fuck or marry, and Gilgamesh has to be kill.
Beowulf apparently makes a habit of wrestling men he just met and hasn't even spoken to, naked, and that's fuck behavior rather than marry.
Which I guess leaves me marrying Sun Wukong by process of elimination.