Doffy's slave auction business.
Really? Let me know when it was revealed that Law was at the slave auction looking for clues about Doflamingo? What did he expect to learn from an auction Doffy wasn't present in? Why didn't he decide to travel to Dressrosa or any of the countries Doffy was selling weapons too instead of attending the slave auction?
There's also the fact that Law fucking hates the marines and the wg for what they did to Flevance. Why wouldn't he go and watch the wg supported slavery auction to reaffirm his hatred? There's your context. shove it up your ass.
Again, the context you have is just headcanon, which you were crying about me using. Where does Law look like he has some seething hatred or resentment during the auction? When does Law even show hatred or resentment to the government in the current timeline anyway? Did it come up with Koby in the rocky port incident? Doesn't seem like it. Did it come up in Punk Hazard? Not really, Law worked with the Marines against anti government activist and hero Vergo San. Did it come up in Dressrosa with Fujitora and Sengoku, no, not really. Law has only been shown wanting revenge on Doflamingo(inb4 Doflamingo is a celestial dragons, Law didn't even know lmao), and now that Doffy is dead, he simply wants to learn history, not revenge for his country. If Oda's intention was for Law to be shown disliking the celestial dragons, he would have given Kidd's line to Law.
Just because he smiled once doesn't make him a slave trader you clown. Other than that, you literally have nothing to frame him as a slavery enjoyer. The reason he keeps smiling is because he's a cheerful guy you dumbfuck.
Maybe, but the fact that he was at a slave auction and looked pretty comfortable in his seat? It doesn't exactly look like it's his first time. Law being at a slave auction with nothing in the manga explaining why he was present makes it likely he has some interest in the slave trade.