even if Xebec tried to force himself on her, everyone else on the rocks crew would be pissed and jump him.
WB, Shiki, etc etc. So it wouldn't be wise to even try something like that. Doffy didn't casually off an admiral, he had no problem forcing himself on women when no one was staring over his back
Oh wait except he was shitting himself from Kaido's shadow, let alone Kaido in person.
"Pirates are supposed to be this! pirates are supposed to be that!" Pirates also do whatever they want if they have the power to have that kind of freedom, but it's a problem when you don't like it. Xebec simply chose to covet Shakky as a treasure of pirate Island, if he acted in the way you wanted him to, rocks pirates would have been split right there and then, because everyone else was fawning over her anyway.
It's better he keep her as a kind of mascot for pirate island, and her bar as a tourist attraction. He could literally leverage her presence there.
Here is your goat glazing the Simp WB
around the same timewhere he asked Mihawk if he was "really going to fight" as if he was too much of a pussy to raise a hand against WB himself and his "incredible power"
He has no problem laughing and smiling about one Yonko when he knows he's not going to directly go against them "Are you really going to fight?"
Yet here is him shitting his pants over Kaido, when he knows there will be real consequences:
Doflamingo is sooooo tough, when the big dogs aren't around. I bet if doffy was around in rocks era he'd be a shakky simp as well, he'd fold and conform to have the same opinion as everyone else, especially anyone whose stronger than him.