Muichiro – Kind, sweet, cheerful and good. Yuichiro – Rude, hot-tempered, and at times angry.Both of them are exactly the same but the characters are different. They have blue eyes, and long black hair down to their waist, the tips of which are blue.They were born into a lumberjack family. The mother died of illness, and the father fell off a cliff. Both are 11 years old.Amana found them and brought them to the headquarters of the demon slayers.Before that,They ate caught fish and cut down trees