During Tanjiro's trial, the leader, also known as "Oyakata-Sama" was introduced and despite his weak appearance, I was quite surprised at how much respect he was able to command from all the pillars and this got me wandering how strong he is (or must've been in his prime).
He mentioned that the Hashiras only acknowledged strength. So this leads to my question, how powerful is "oyakata sama" comparatively to the upper Moons and how did he get the "Byakugan-like" curse on his face.
Also (just in case he was never a force to be reckoned with), why would someone so weak be chosen to be the head of such a powerful organization? and how was he able to tame the Hashiras.