@Bigivel:
That was only one thing that Lao G said, and his opinion. Taking it to be Doflamingo and the others members of the family opinion and reason for her is the wrong way to see it. Specially when we were shown to Law and Doflamingo Flashback and we know very well how Doflamingo seen the kids and why he allowed them to be with him as a family.
This is like totally deforming the opinion of a particular person and/or a group of people just because of a comment of one of the members. And not even a influential one in the group.
It is only Lao G who speaks on the matter yes, but since his one line is the beginning and ending of the matter its not really made clear if its a general family viewpoint (supported by Odas SBS comments of Doflamingo using broken people to his advantage, further muddling the Doflamingo family characterization) or a Lao G specific viewpoint. Aside from Lao Gs words the most we get of a reaction to Baby 5 afterwards is Pica going "you betrayed us, huh" and trying to kill her, so its hard to tell if they saw her as a tool or not. Ots just the final note we're left with before she ditches the family and never looks back.
@Bigivel:
"She's a super sexy french maid who will do absolutely anything you ask wink wink", where was ever shown or depicted that to be her stick?
Obviously a manga aimed at young boys isn't going to directly say that people could just ask Baby 5 to fuck and she'd say yes (though she does seem custom made for hentai artists). But her character is still a standard issue Oda bombshell of legs, boobs and a pretty face whos custom outfit is a popular fetish getup, and whos main quirk is not being able to say no what people ask. Mostly men. Including old disgusting men, and we are invited to laugh at how this sexy girl will accept literally anyone. The joke is that she's super sexy and capable- but will still do anything you want!
With everything from Hancock being lovey-dovey, to gawking at Shirahoshis boobs to Sanjis hot sister frenching Luffy to even Jora or Brulee going on about appearances, Odas female characters are almost always linked to tired, generic female attributes such as love and looks, and a hot french maid who will marry anyone isn't helping with that statistic.
@Bigivel:
"It being contextualized later doesn't change the punchline she was earlier", yep that punchline that was trying to murder Doflamingo and that got shot point-blank. That also doesn't change Senor Pink, nor any other fictional character where later Flashback that further explains the reason for this character weird actions.
Recontextualization can be a powerful thing, and recontextualizing jokes can absolutely work. Its just that the Baby 5 joke was really, really, really cringeworthy. Rereading her scenes, am I now supposed to feel sorrowful sympathy for her during the "Disgusting man literally made of snot whom nobody can stand being close to jokingly makes a pass at her and Baby 5 instantly buys into it with stars in her eyes going "do you need me?" with a little heart visual effect get it haha the sexy maid is ready to throw herself at the snot-man"-joke through the power of added context? It doesn't work like that.
@Bigivel:
"The resolution to her neuroses" who said and where it was ever presented this was Baby 5 "resolution to her neuroses"?
"The last man she submits", the submissive woman card. So where was shown any submission? The opposite was shown she imposed on him.
She overanalyzed him, Hancock -style, and arrived at the conclusion he was coming on to her. Then in the end Sai announces he will marry her, and Baby 5 instanly accepts it, just as she did with every other instantly proposing man she'd met. Just because its not directly verbalized doesn't mean that Baby 5 isn't going to approach the relationship caring to Sais every demand in an attempt to please him and feel needed, because thats her character, and theres no indication that she ever moves beyond that. We can assume that Sai won't treat her badly, and that is the ultimate resolution for Baby 5's character, her goofy, puppy-love romantic end. There is no sign that she doesn't still define herself entirely through catering to a man…its just a nicer one this time.