The Super Secret Pup Club is a puppy-placement group. Originally created by Patches, Rebound and Cupcake when the latter two were told that they were "too young" to find homes for pups, the Club now serve to help the Shelter 17Pound Puppies.
The Club's next appearance is in the episode "The Ruff Ruff Bunch", which revolved mainly around Rebound joining the titular "bunch," and convincing the other two members of the SSPC to join.
In "Salty", the three find the titular character looking for a replacement for his human, so they dress up as potential replacements and purposely fail in order to attempt to show him that he can't be replaced.
In "Squawk", Niblet takes the Club and Humphrey to see a vat full of peanut butter. Later, the pups help Niblet look for Napoleon around town.
"The Accidental Pup Star" has Rebound nearly reveal the fact that dogs can talk through an internet video. The other two members mention that they both starred in internet videos of them falling into their owner's toilets.