- Kumiko's various reactions to things, from flustered/panicky to thoughtlessly rude.
- People covering Kumiko's mouth after she accidentally says something rude.
- Asuka's theatricalness, Gratuitous English, and Double Entendres.
- Episode 1: The Brick Joke of Hazuki finally realizing what Kumiko had meant by "they're terrible". Kumiko just looks at her in response.
- Episode 2: Hazuki fitting her mouthpiece to the tuba is accompanied by an animation of a foot sliding into a glass slipper.
- Hazuki names her tuba "Tubacabra".
- Gotou's overly simplistic description of the tuba.
- And Asuka's overly long description of the euphonium.
- After being called to the back of the school by Reina in episode 4, the look on Kumiko's face◊ as she fears she's being led back there to be murdered. Only to then have Reina apologize for acting rude to her the previous day.
- After she does this, she bolts out of there as fast as she can run.
- Prior to the ensemble performance that will determine whether Taki allows the band to go to SunFes, one of the horn players comments that if he doesn't pass them after all the crap they've been through, she'll throw her mouthpiece at him. Following the performance there is a quick shot of her starting to remove it in preparation for throwing.
- When Mr. Taki makes the bandmembers do a lap at the courtyard, Kumiko is seen struggling to run, Reina flies past her and Midori is "running" at a turtle pace.
- Episode 6: Asuka gets Kumiko to dress up as Tuba-kun to cheer up Hazuki. What ends up happening is that Sapphire sees Kumiko in the costume and immediately tackles her in a hug.
- Hazuki's Imagine Spot about being outperformed by new tuba players, who she pictures as recolored Sapphire clones named Ruby and Platinum Diamond.Hazuki: No way... Midori, you suck!
- Episode 7: Kumiko and Shuichi taking a couple seconds to notice that Reina is suddenly sitting near them, then being appropriately startled.
- Episode 8: Kumiko teasing Reina about not minding pain.
- Episode 11: Kumiko overhears Reina and Yuko talking in private. When Reina starts to leave the room, Kumiko panics briefly. Before Reina walks past, she hides by hunching over in a corner of the hall, facing the wall.
- Natsuki sneaking up on Yuko and then being chased away by her.
- Episode 12: Natsuki's charm to Yuko. It's the biggest, because she made it with love. The love of harassment.
- In the season 2 opening, there's a split second of Natsuki covering up the camera with her hand, annoyed that she's being filmed.
- Yuko and Natsuki's Gratuitous English shirts in S2 E2. Yuko points out Natsuki's ("Cement Addiction") and Natsuki points out that her own ("My Staple Food Is Love") is just as silly. Yuko angrily brushes it off, saying they're in Japan anyway, so who cares what the English says?
- After a serious discussion with Nozomi, Kumiko realizes that she left her friends waiting, and it cuts back to show them wondering where she is.
- If you look closely, you can see that Reina got ice cream for both herself and Kumiko, but she's been waiting so long that she's finished hers and has started on Kumiko's.
- S2 E3: Kumiko tries to hide when Yuko walks past. By facing a wall and flattening herself against it, leaving herself in plain view. It doesn't work.
- In the same episode, Yuuko earnestly asks Kumiko whether or not she hates her. Kumiko's response?
- Reina and Yuko calling each other "senpai" and "kohai".
- S2 E9: Natsuki wants Kumiko to try to persuade Asuka's mom. She tells Kumiko that it'll be okay. Kumiko, skeptical, tells her to say that to her face. Natsuki avoids looking at her and says "Okay."