Blackbeard will become the next Pirate King. Proof is in Demalo Black

Demalo Black's inclusion in the story is weird. He is not a real villain, an obstacle or even a threat. He seems like a completely useless character until you realise that he foreshadows Blackbeard becoming the King of the Pirates.

Parallels Between Demalo Black and Blackbeard

Oda's MO is using parallels and common narratives throughout the story to connect themes, places, and characters. Demalo Black and Blackbeard share some striking similarities:

1. They both act in similar dishonest ways: Demalo tricks people to join him, relies on intimidating opponents in hopes they back down. Blackbeard steals devil fruits, rigs situations in his favor, goes after weakened enemies and refuses to fight strong foes.
2. Demalo's and Blackbeard's crews:
   a. Demalo's crew is an obvious copy of the Strawhats. Blackbeard's crew lines up perfectly with the Strawhats, even with some clear matchups.
   b. Caribou was one of Demalo's recruits, now he is on Blackbeard's side.
   c. Demalo had a pet fox. But why did he have a fox if Chopper is usually mistaken for a raccoon? That's because of Catarina Devon's fruit, the "Nine-Tailed Fox".
3. Demalo BLACK, BLACKbeard.
4. They have similar builds.
5. Demalo's epithet is "Three-Tongued". There's a motif of 3's with Blackbeard: three skulls, three pistols.

Demalo's past and Blackbeard's Future

Demalo Black pretended to be Luffy on the last island of Paradise, Sabaody. Blackbeard will become the "Pirate King" on the last island of the New World, Laugh Tale. He will lack certain attributes and qualities of the real Pirate King, just like Demalo was not the real Luffy.

When Luffy revealed himself on Sabaody, Demalo's jig was up. When Luffy defeats Blackbeard, the "Pirate King", he will become the true Pirate King.

Oda loves unexpected twists and surprising the reader. What could be a bigger shock than Blackbeard becoming the next Pirate King?

Speculation on how the story will go

While Luffy, Dragon, Shanks, and the others are busy fighting Imu, God's Knights, and the marines on Mary Geoise, Blackbeard will take advantage of the chaos, reaching Laugh Tale without any resistance. He will claim that he found the One Piece and declare himself the Pirate King.

P.S. There are some more parallels that I think are either weak or a stretch. Still, there may be something interesting:

1. The first time Nami met Demalo and Blackbeard was in the bar
2. After meeting Blackbeard, the Strawhats go up 10km. After meeting Demalo, they go down 10km.
3. a. Demalo Black is named after black coffee (some of his crew is also named after coffee/drinks: Drip, Cocoa, Chocolat). Blackbeard is said to never sleep.
   b. Wait a second... He is named after coffee, huh... Who loves coffee? Robin! What does she also love? Archaeology! Whose hobby is Archaeology? Blackbeard's! Boom! There's a solid, legit, 100% debunk-proof connection! Thanks, Robin!