The reasons Dabi is Shoto's eldest brother Toya since his origins are unknown. Also Dabi knows the game Shogi and hates fish.
1. He knew Shoto's and Endeavor's real names.
2. Dabi has blue flames which is stronger and hotter and a flashback in Chapter 202 reveals that Toya's Fire Quirk was stronger than Endeavor's Hellflame. The canon name of his quirk is still unknown.
3. Dabi's quirk is like Izuku with One for All as both quirks are too much for their bodies to handle which results in purple colored skin it could even happen to Shoto (even with his ice side) or Endeavor since blue fire is stronger than red-orange fire.
4. Dabi's eye's are full turquoise like Enji's and Shoto's left side and his face resembles young Enji too.
5. In Chapter 191…Read more >