Science behind kissing question?

if you're kissing someone and somehow you like the taste of their lips more than, say an ex, does that mean your's and this new guy's (that your kissing) genetics are more compatible to create babies? Because its kind of weird, but i didn't quite like how my ex's kisses tasted. Even if he brushed and swished with mouthwash. But this other guy that I used to like, his kisses were yummy. haha! so does that mean mine and my old crush's pheromones or whatever are better suited for each other? Just curious