Sanji using Diable Jambe has always been a spectacle ever since it was first introduced. It gave Sanji a unique edge that perfectly fits with his personality.
Diable Jambe has undergone a lot of improvement since it started. Sanji uses it to enhance his already powerful kicks to another level.
Sanji’s flames get hotter the angrier he gets. Sanji started with red flames as stated by Jyabura when he first used Diable Jambe on Enies Lobby, which are the not very hot.
During the time skip, these became much hotter, yellow usually and white in the raid suit. Now, the only thing that surpasses this, in the time of a fight, would be a blue flame that would be the hottest flame by far.
Diable Jambe means “Devil’s Leg”. Blue Flames are often used to represent the devil or Satan. “Aoi hono” or “Blue flame” is also an idiomatic term in Japanese for something exceeding the usual limit. Obviously, it does mean a physically blue flame as well.
In an SBS, Oda mentions specific colours for each of the Straw Hats. You guessed it, right. Sanji’s colour is blue.
All of Sanji’s fights are against opponents that are similar to him in certain ways:
- Kuroobi and Sanji were the only two characters to use a specific martial art style, Kuroobi using Fishman Karate and Sanji using the Black Leg Style.
- Wanze and Sanji both were chefs who took great care of their knives.
- Jyabura and Sanji were both regarded as the third strongest member of their crew, Jyabur after Lucci and Kaku and Sanji after Luffy and Zoro, but made up for it in a better and diiferent way, Jyabura with his devil fruit experience and Sanji with his iintelligence.
- Absalom and Sanji were both absolute perverts who would want to peep in a women’s bath.
- This is usually valid to the smallest of skirmishes Sanji enters like Duval who looked very similar to him.
Currently, Sanji has a part of his identity hidden, he wears a mask, a suit and goggles, has something concerning fire, he was asked to join Big Mom’s crew but refused bluntly. Sanji is calm and collected and thinks things through, intelligent and a pervert.
King, currently, has a part of his identity hidden, he wears a mask, a suit and goggles, has something concerning fire, he was asked to join Big Mom’s crew but refused bluntly.
He is calm and collected and thinks things through, intelligent and a pervert, more specifically, a “torture-loving pervert”.
King in the latest episode, 972 was showing holding a blue flame. This was quite likely an effect King had on the flame. If this is true, it would have a similar effect on Sanji’s flames making them blue in his surroundings.
Sanji has no qualms becoming the devil. Sanji said that if something happened to Nami-san, he will become the devil of the blue sea.
On Thriller Bark, when Usopp tells Sanji that an invisible man peeked on Nami bathing, Sanji immediately erupts into flames and explodes. Zoro says, “Don’t excite him anymore. He might transform into something.”
Sanji, if he is angered enough, might transform into the “Devil of the Blue Sea”.