Entirely self motivated, but with the current state of blood vials not lasting between resets, getting useful ones is difficult. So I suggest the following
Added to Level 5
Blood Drain Player Tool x/day (Whatever DMs think is balanced)
Medium or Long range.
Target Player must make a DC X (Again, whatever is balanced) Fortitude Saving Throw, having a vial of their blood added to the caster's inventory and taking damage as if drained by a syringe on a failure.
Caster and target player both display a message indication.
This is Thematic for the Perk, and Enables easier use of both the Level 1 and Level 8 Player tools, especially as vials cannot currently be saved.