Bound Male Dog gets tickled and horny

This was not imagination of our male dog when she get strapped with chains to the rubber bed by the Master. Even if he defends himself against it, his hind legs are wrapped in foil. The Master tickles the hind paws what makes the dog squirm a lot. When the speech on bitches in heat comes, he pants completely enthusiastically. But the master still plays a little with the almost stiff tail of the dog and leaves him then pitifully barking back for...