When you think about how the relationship between Monet and Caesar began it starts to become curious when exactly it did commence. The story implies Monet joined Caesar after he escaped the Marines and returned to Punk Hazard but when you look deeper into that narration, certain discrepancies arise. Would it not be odd if after escaping the Marines and fleeing back to Punk Hazard a year later a stranger Caesar has never met before arrived on an Island that should not exist housing the government’s former secret research facility and requested to work for him? Regardless of Caesar’s twisted nature, he is still a genius and would immediately be suspect of such a person if not kill them on the spot. It is just suspicious. Such a narration really doesn’t add up when looking at the relationship Monet and Caesar shared throughout the Punk Hazard Arc.
Monet could have a similar story to Brownbeard’s where she was injured and ended up shipwrecked on Punk Hazard but I don’t see the same story being recycled. And that wouldn’t explain the casual relationship Caesar has with Monet to the point of not even making an effort to hide the truth concerning his experiment from four years ago when speaking to her. A truth that he purposefully keeps hidden from the rest of his subordinates by changing the narrative of what happened on Punk Hazard in the past to portray Vegapunk as the heartless mad scientist. Monet is the only person Caesar has shown to consult in and listen to – assisting with Law’s proposition, heeding her recommendation to not take the Straw Hat Pirates lightly and to retreat when Luffy was after him. Caesar meeting Monet through an introduction by Joker also wouldn’t work as that scenario would set red flags off in Caesar’s mind concerning a connection between Joker and Monet. The only logical conclusion I can deduce that would explain the relationship Monet and Caesar share is having a prior connection before Caesar set off the explosion four years ago. Oda-sensei doesn’t specify when Monet’s mission began, he only has Vergo-san mention that Doflamingo went through the trouble of planting Monet undercover on Punk Hazard. Monet’s mission beginning before Punk Hazard was sealed wouldn’t change anything from the Punk Hazard Arc, instead it could help explain certain developments left vague. Caesar didn’t bother to hide the truth from Monet regarding his actions from four years ago because she was already cognizant of the incident. Having worked alongside Caesar in some form in the past made him open to Monet assisting him again after being arrested by the Marines and having a bounty issued. Monet may have intentionally positioned herself as an ally of Caesar’s (as was her mission) so that when such a scenario arose, Caesar would naturally trust her.
Monet potentially is also responsible for Caesar’s escape from the Prison Ship that he was detained on. The fact that Caesar was apprehended and taken aboard a prison ship suggest some level of restraint by the Marines, otherwise I doubt the reactionary Caesar would have kept himself passive as he was dragged out of the Punk Hazard facility and onto the prison ship. If Caesar was able to use his Gasu Gasu no Mi abilities during the transition from the Island to the prison ship, he would have. Lets also not forget that Punk Hazard housed the government’s secret science laboratories which the Punk Hazard Arc has shown to have contained seastone bindings. On top of that, Vegapunk already intended to banish Caesar before the incident and had called the Marines to the lab in advance to escort Caesar out. When Caesar was arrested after setting off his experiment, there would have been no issue with the Marines using one of the seastone bindings in the Punk Hazard lab to restrain Caesar and prevent him from escaping or doing anything even more foolish. With Caesar secure on the prison ship being transferred to potentially Enies Lobby, there should have been no issue but what if Monet also boarded that ship as a government researcher fleeing the poison gas blanketing the Island? Could that not explain how even after being apprehended and restrained on a prison ship, Caesar was still able to escape? Unbeknownst to those aboard the prison ship, Monet may have utlised her abilities to put Caesar’s prison guards to sleep and break him out. After Caesar (gas form) and Monet (snow form) escaped from the prison ship, this would be where they (Caesar) met Joker.
Doflamingo aware of Caesar’s status through Monet could have approached him proceeding his escape and bounty issue with a proposition (without having Monet sacrifice any of her cover by mentioning Joker). Unable to refuse and overwhelmed by the prospect of having his own research funded by the most influential broker in the underworld, Caesar agreed to enter into an arrangement with Doflamingo. This is where the concept of SMILE began taking shape. Spending the next year on Dressrosa away from the eyes of the Marines, Caesar (and Monet) built the SMILE production factory. After that one year (three years before the Punk Hazard Arc story), Caesar and Monet traveled to Punk Hazard to set-up Caesar’s lab within lab 3 (Vegapunk’s former research lab) where the SAD was to be produced. Upon arriving, Caesar (and Monet) encountered the former Punk Hazard prisoners. Caesar subsequently used his abilities to clear the poison gas and build the injured prisoners balloon platforms to move around on. Honestly, I would not be surprised if it was Monet who recommended the use of balloons to assist the injured prisoners who lost the use of their legs as a result of being paralysed from the waist down due to Caesar’s poison gas. Caesar may have desired to finish off the prisoners but succumbed to Monet’s rationale of saving the injured prisoners and using them as him subordinates. From this point forward, Caesar commenced working on his SAD formula and producing his Shinokuni gas. The gigantification experiments commissioned by Big Mom using young children also began – Monet was present three years ago when Mocha and Sind were first brought to the Punk Hazard facility already working alongside Caesar.
In addition to Monet working her way into Caesar’s inner circle, Monet’s undercover role as a Punk Hazard researcher while still operated by the Marines could have also been to provide Doflamingo with information concerning the Marines and the World Government’s scientific advancements. Doflamingo knew about Kuma’s circumstances and what the World Government did to him. Doflamingo was even aware of the top secret Pacifista project before it was even revealed during the Marineford War and possessed information more extensive than what the rumours the Whitebeard Pirates heard had contained. Without having inside information, it seems doubtful Doflamingo would have awareness of such scientific developments and detailed information on Kuma’s involvement. The reason behind such discernment could be a result of Monet being sent on the undercover mission within the Punk Hazard facility where research on the Pacifista and Kuma-restructuring project were being undertaken or at least had information contained in. Vergo, as a Marine Vice-Admiral, may have been used after the Punk Hazard incident to keep Doflamingo up to date on the later developments involving Kuma. It would explain why Doflamingo was so informed about such sensitive information. Further, if this is the case, Monet could provide some answers on what happened with Kuma and why.
Monet’s story is incredibly mysterious and when looking deeper at major events surrounding Punk Hazard, her presence would help explain certain gaps currently left vague. With Caesar and Monet’s relationship, I am inclined to believe it began long before Caesar returned to Punk Hazard and began working on his SAD formula. I believe it originated when Punk Hazard was still operated by the World Government and the Marines prior to the incident four years ago. And if this is the case, Monet may have further knowledge into Vegapunk and the research he was working on. When Vegapunk does become the focal point of the story, Monet could become relevant again.