Everyone has a soulmate mark.

And yours was on your right shoulder a zanpakutō with the name "Kyōka Suigetsu" under it...

You're a soul reaper that's in the 8th squad... And you have your Bankai and Shikai... So you get sent on more missions then other squad members.

Today You got sent to Las Noches to get intell on Aizen, as you were walking through the hallway trying to be as quiet as you can cause the espada's are around... When a zanpakutō got placed at your neck...