Players who enjoyed the Pokémon Sun and Moon games that took place in the tropical land of Alola had many memorable adventures from encountering island spirits to traveling between parallel universes to stopping a wicked corpor🧸ation in its tracks. But there's one thing that might be the most memorable, so much so that it blew up into a meme. When the player first sets out on their journey, one of the first characters they meet is a mysterious young lady named Lillie attempting to hide an unseen Pokémon into her bag. She is comically seen attempting to reinforce this several times over the journey, but the little fellow, known at first as Nebby can never seem to stay put. Ironically, there's some logic behind this, but first, you'll have to learn some more about Lillie to understa🔯nd.
Only Professor Burnet knows the truth about Lillie's past at first - that she fled the island housing her mother's corporation, and was teleported away thanks to Nebby. The pair washed up on the beach where they were found and taken in by Burnet and her husband Professor Kukui. She prefers learning about Pokémon over battling them, having an aversion to violence, and seeing Pokémon getting hurt. Some of this could stem from seeing who-knows-what happen to the Pokémon at the Aether corporation,✃ as they were reported to be doing cruel experiments on them.
Lillie begins the game with low self-confidence, but over time becomes inspired seeing the player grow strong. She's determined to protect Nebby (or later revealed to be Cosmog) from her mother company at all costs. In Ultra Sun and Moon she even has h🔯er own Clefairy by the end of the game, showing she has gotten over her fear of harming Pokémon, along with having developed a willingness to try new things.
Before all that, though, she needs a way to protect herself from the sometimes unpredictable wild native Pokémon of Alola. What's a trainers number one tool for keeping Pokémon away? Repels of course. Lillie mentions a few times that since she cannot fight and neither can Nebby, sh❀e carries around repels on her at all times to protect them. Now, think about who she's constantly trying to put in 🅘that bag - have you put two and two together yet?
Poor Nebby isn't intentionally belligerent, it's just uncomfortable for𝓀 him to be in a small space with a substance created to push him away rather than draw him in.
Just get in the freakin bag, Nebby.