New Slave

In this fictional story a young dominant married couple accepts the service of a willing male slave who is new to BDSM to take care of household chores. The relationship quickly grows to include consensual torture as the slave's endurance is pushed to the limit. The story is written from the wife's point of view.
Excerpt:
Mark began swinging his whip with his fast whirling motion and rained down over a dozen blows in quick succession followed by a few hard strikes between pauses. I really enjoy watching Mark in action.
I prepared my implement and powered it on as Mark stepped aside. I contemplated an application to slave’s bright red back but decided on an upper arm instead.
Our slave never saw it coming. Zap! The violet wand worked its magic and slave yelped in surprise and pain.