Focus: Yorichii Tanjuro Kamado
Persona: Faather Of Tanjiro Kamado
Anime: Demon Slayer (Manga)
Yoriichi was undisputedly faster than Muzan, who himself was far ahead in speed than the hashira, who can move faster than the eye can perceive, as stated several times throughout the series. To move faster than the human eye can track, you have to travel at 17500 miles a second, or 38146 mph. Even the hashira, who can move that fast, couldn’t even see Muzan’s attacks. For him to be imperceptible even to their eyes, he had to have been at least twice as fast, which would be 76292 mph. An again, Muzan couldn’t perceive Yoriichi’s movements, so doubling that speed once more would be 152584 mph. That's how fast a sword swing from Yoriichi would be. As explained in the manga scan above, Yoriichi cut 1500 separate pieces of Muzan’s flesh on the spot, we’ll say about a second. That’s 1500 sword swings, each at a speed of 152584mph, or 68211 miles per second, in one second. That would be 102,316,500 miles per second or 228875492 mph. That’s roughly 300,756 times faster than the speed of sound. Yoriichi can move at 300,756x the speed of sound. Let that sink in. That’s why he’s the most powerful, particularly in a universe where speed is key.