[quote=Dark Eternity]
The Resonance sounds like a basic drain attack, leaving the user heavily unguarded, as it requires the Meister to keep Jacholaus impaled within the enemy. Small fry will die fast, while stronger enemies can withstand short exposure to the attack.
[/quote]

But the faults of that are:

If energy is too strong, then it resorts to blood. No matter how strong you are, the body still has a limited amount of blood it can hold. And although you could pull the blade out, the blade siphons blood, so if you pull the blade out (Unless there's a healer around, or a hospital close by) then you're still risking death by letting blood out of the wound especially depending on how deep the wound is.

But even so, I'm not sure how'd you'd be able to pull the blade out if blood is violently being siphoned out of your body with someone on the other end forcing the blade into your body unless the character is a brute character but the fault of that is...Even the loss of blood could weaken a strong man lessening his chances of pulling the blade out (Unless Jacholaus is a physically weak man, although I'm sure if that was the case then he wouldn't be able to pierce an enemy unless the blade is very sharp all around).

Though, you are the GM, and if you're fine with the ability then I'll drop it.