I like it a lot. The Spellcasting requirement seems a bit easy though (in that all casters are likely to have those ranks). How about a feat instead? Guts? Bandage? Dark Ritual (from the CtA: Infernalist pdf) would fit very well.
I was thinking about those, as well as Combat Vitality as possible pre-reqs. Will ponder mroe and ammend.
I'd like to see an ability that boosts the Save DC against your spells against any target that is bleeding.  Just noticed Bloody Breach. I think that's meant to do the same thing, but it's not very clear what the penalty is to
Bloody Breach is supposed to cover that, I'll try figure out a clear way to write it.
When this ability ends you become Fatigued and Sickened for the remainder of the adventure.
Oh snap. That's positively nasty.
I wanted it to be a "think seriously about using it" ability. It could kill you, and if it doesn't, it could definately limit your usefulnes for a period of time. I was also going to make the user Stunned
for a number of rounds equal to the time it was active. Changed my mind at the last second.