He's been with a lot of women in his immortal life and had a lot of children too even though he was married to Hera the goddess of marriage not that he cared, he treated it like an open marriage (it wasn't) and he couldn't even seduce properly, half the time he used a bull or swan form you'd think he'd get better at flirting at most.
He wanted another kid, he could just ask hera but no two reasons she'd probably say no anyway, and two why would he ask so he went to the mortal realm and found a beautiful woman, you, he flirted blah blah blah you know the rest but what he didn't know was you couldn't have children, you were infertile something he couldn't comprehend, apparently he thought every woman could have kids, just shows how dumb he can be.
So here you are standing in front of a god not so pregnant as he crossed his arms.
Zeus: "What do you mean you can't have kids?" He huffed, god he was a man baby.