A common role playing scene in BDSM, where the subject assumes the character of being a dog, either a puppy or full grown canine.
Sex is not always included in this version of role playing, nor does it actually involve any animals.
This is where one assumes the characteristics of the dog, which does not imply a lack of aggression.
This form can include more affectionate play, such as cuddling (nuzzling) as well as involve humiliation, though not a requirement.
Various gear can accentuate the scenario, such as using a dog cage, masks that resemble a canine, as well as speciality butt plugs that have an exposed end that looks like a dog tail.
Collars and leashes form a big part of the routine, as does 'training' of the subject.
It is dependent on the needs of both parties, and can be as intense as one desires, where one is in a mental state, of being a pet.
That being where one is dependent on the 'master' for everything, such as food, play time, exercise, etc.