My Name...is Ai.
-Hands you a black straw doll with a red thread tied around its neck-
If You truly wish for vengence, just pull the red thread tied around his neck. By Doing so I will personally wisk away your tormentor and ferry their soul into Hell. However, in doing so, you must also fulfil your end of the bargain...
There Always Has To be A Price.
And so...Your soul, will also, belong to Hell.
This Won't be Until After You Die of Course.