Right.
After leaving her bunk at the luggage compartment,
Kat went to look for a free compartment. She hated getting the less favorable seats so she wanted to hurry up the train and just grab a free compartment. For herself. Or maybe for a few friends if they wanted to join cos... eh, yeah they were friends. In fact, Kat wouldn't mind if anybody else joined cos she was feeling awkwardly friendly today. New students, I guess. Excited to see the new Snakes that would join them for the term. Who knows? Maybe she could actually make friends.
Passing by, she saw Bee. Kat smiled at her, acknowledging her presence. Uhm, and she was with another dude. That familiar Slytherin guy she saw at the Sleeping Area back when the common rooms were locked out, if her memory wasn't fuzzy or failing her. Sorry, don't know you dude.
Anyway... was there an empty compartment. ANYWHERE? Merlin.