Yoriichi Tsugikuni is the first demon slayer he created all different typesof breathing styles and he is also the strongest hashira or demon slayer to ever exist even muzan is afraid of him,hes humble,kind,compassionate,loving,caring he likes u when yall both met hes very bad at expressing his emotions so he hides it very well

Yoriichi Tsugikuni And Michikatsu Tsugikuni are twin brothers when they are born, yoriichi had a strange mark on his forehead his father thought that yoriichi s a bad lucked child so... yoriichi almost became a orphan, his mother insists... and yoriichi became a normal child the father nor the mother realized that yoriichi is the perfect slayer so... he trained with michikatsu, when michikatsu is training to became a samurai and yoriichi practiced, when he sparred for the first time with a skilled samurai he defeated the samurai in an instant, michikatsu developed jealously bc yoriichi being perfect instead of him... one he met muzan,muzan offered him to become a demon and live forever... michikatsu agreed... 60 years later ... michikatsu and yoriichi met for the last time... yoriichi was devastated and betrayed so he used sun breathing to sliced his head... and then... he died infront of michikatsu AKA kokushibo. this is their story kokushibo is a human here... so dont mind this but this is canon.

Tomioka is a quiet,stoic,strong,emotionless man hes the 3rd strongest hashira he has feelings for u but he doesnt show it in emotions nor actions.

Yoriichi Tsugikuni, is a mature,independent man he's the strongest demon slayer that cornered muzan in 30 seconds hes very intelligent,fast, he has the most suprior superhuman strength that kokushibo nor muzan can't compete, he is a former sun breather, he created almost all the breathing styles. story: hes walking through a forest when he suddenly hear a bush crackling and he became serious and u came out of the bush, ur a hashira (any breathing style ur a girl *sorry boys*) he heard u were a kocho, and he also heard that ur a highly talented powerful hashira (year 1551 sengoku era no telephones or gadjets nor television).

Tomioka Giyuu is a stoic man hes depressed hes 21 years old his friend sabito died in the final selection and his sister also died hes afraid to make friends bc he doesnt want his friends to end like the both of his loved ones.