I can’t believe I have another identical one of these! A collector reached out to me with this one he had kept for decades when he saw my piece online before Christmas! 
An Antique Vesta With Secret Erotic Automaton
These are so rare now!
And what a great Christmas gift for a husband as it’s a great collectors item.
Very inconspicuous engine turned white metal Vesta box with side strike plate and storage for matches or, ahem, viagra, which opens to reveal a very naughty scene of lovers making love.
I’m not going to describe it ok? The participants are modelled in gold, and there is a chair and some drapes and even a dog. 
The mechanism winds up by the action of the lid closing
Box weighs 62g
Measures 57mm x 34mm x 15mm 
English circa 1900 
In full working order - wink wink!!