Shield bash can be used to block Fenrir's 2hr.
PLD/SAM + staff and switch to sword/shield when TE is down? Probably won't deal enough damage to beat Fenrir in 30mins.
Not that I'm supporting the idea.. Because it still sounds a tad outlandish to be able to deal enough damage in a thirty-minute window with a staff, but Seigen caters to high-speed situations.