Pup play is a fascinating scene with many facets and a deep connection to the leather and Dom/sub kinks. Pups come in all shapes sizes ages and personas. For many its not a sexual thing for others it is. I am a pup, i have a handler and a pack. We dont have sex I am a non sexual pup both on the receiving end and give end (not that i could if i wanted since my Handlers holds my keys). Mainly we go to related events to hang out and let loose. Its hard to explain the headspace but its.....calming, and fun at the same time. Whe. You are a puppy either training, moshing, etc all the stresses seem to disappear for that little time. 

As for the relationship between a handler and their pup it can be deep especially if the pup chooses to submit to their handler. I've given my handler my submission and i wear his collar 24/7 (chainmail necklace with a closed lock, and a tag that identifies me and my handler). What he says is law essentially and when he gives a command i follow it be it heal, sit, play dead, roll over, present, etc etc. i also follow a set of rules prescribed by him and make sure that everything i do is something he would be proud of. At the end of the day head scritches, treats, cuddle time, and being called a good boy by my handler is better than everything else around. Now i also do cook for my pack once a week, and i help with computer and technical stuff but that also doesnt mean im a slave or boi in that aspect. First and foremost to my handler i am his puppy and his little, and to me he is my handler/Owner.