Yojimbo is an aeon that you can get before you climb that mountain. Remember where you fought that rock thing. There was a bridge and another road that leads below it. Take that road to get yojimbo. If you do not have him I highly suggest you get him before you defeat the boss you are stuck on. If you need further help in obtaining him just as again.
Lets live together, I don't know how long it will last, but it doesn't have to be for show, together, till death do us part. - Kenshin "Shinta" Himura - Rurouni Kenshin