A charming text conversation with my brother

Rachel ("Puma") is our 28-year-old cousin, Brad is her younger brother, and "Mongoose" is her boyfriend. No one can figure out what the stupid nicknames are all about. She swears she has explained it before; she definitely hasn't. Next weekend we are driving out of town for our annual three-day family reunion and because my brother's wife can't come because of work commitments, he will be riding in our car. My grandma is trying to fit him into Brad and Mongoose's hotel room, but he'd rather stay anywhere but with them, so he'll be staying in our room instead. Here, we discuss the pertinent details.
Kirsten: Matt would like to know what kind of music you like, for road-trip planning purposes.
Judge: Folky singer-songwriter stuff. Andy Davis, David Ramirez. I also prefer really really sad music. Not good for road trips. Bob Dylan.
Kirsten: All my favorite songs are really sad.
Judge: We can cry together. Townes van Zandt?
Kirsten: You're dismissed from this music planning meeting. Also, what's the big deal about staying with Brad and Mongoose?
Judge: 1) Brad doesn't talk. 2) Mongoose is ultra-conservative. 3) Brad is very skinny. You can't trust people who are that skinny. 4) What if Mongoose has a terrible time? 5) We're calling him Mongoose. That's absurd.
Kirsten: Matt thinks "Mongoose" is a euphemism. He says mongeese eat snakes. Nudge nudge.
Judge: Oh dear. Well, nobody has mistaken anything about me for a snake. Nudge nudge.
Kirsten: Well what's the "Puma" part about?
Judge: "Puma" is sometimes used as a replacement for "cougar." Like when young men go "puma hunting." But Rachel looks and acts like a little girl. Doesn't make sense.
Kirsten: And Mongoose is older than her anyway. That's dumb. I bet they had a heart-to-heart where they were like, "If this relationship is going to be successful we have to have pet names. What's the most obscure animal you can think of?" Matt and I discuss this often. Rachel is a unique person in that she legitimately watches the Disney Channel for her own entertainment, but she also knits and loves things decorated with cats. And wears cardigans 365 days a year. So her age really averages out to be about 30.
Judge: Have you read the story Rikki Tikki Tavi? That's a charming mongoose.