When Kazuki first meets Kaguya, she covers his eyes and tells him to guess who it is. She then offers him a spa trip for winning, threatens to go Yandere, and then skips six numbers in the countdown before revealing that they've never met before.
During Mio's initial Tsundere phase, she tells Kazuki (who's practicing magic control by moving water in a bucket) to swirl it around with his sword. Kazuki immediately calls her on this. After all, the sword would rust.
In an unofficial manga translation of that scene, Mio proclaims that she'll take the world by storm by casting Kaboom.
Volume 3
After losing to Kohaku and getting booted from the Student Council Kanae insists everyone call her Kana-Nyan-Senpai and spends all her time "making up" for neglecting Kazuki.
Hikaru constantly referring to her relationship with Kazuki as a friendship between men.
Chapter 1, part 4, has Koyuki wake up from a magically induced, over exertion coma to see Mio and Lotte, in maid (and animal themed) cosplay arguing over who was better at licking Kazuki, and deadpans the whole time while trying to come to grips with it.
Kazuha is called the Mikohime by the Sword Division and lives apart from the other students. Which is a nice way of saying her only friends are her summon and Kohaku.
Beatrix retreats by carrying Eleanora and Damian while using Thor's buffs. In the manga version of this scene, Eleanora and Damian are drawn in chibi form while carried.
In Vol 3, Kazuki returns to his room only to find Hikaru and Leme practicing wrestling moves.
Volume 4
The entirety of the video game contest between Kazuki and Hikaru.
When Kazuki's team turns the tide against Kaguya's team, Kaguya and Kanae both go down while calling Kazuki an idiot.
Volume 5
When campaigning for Kazuki's bid to become SCP, Mio makes a poster with a Shoujo manga style illustration of Kazuki. Kazuki notes how unrealistic the proportions look.
Volume 8
Miyabi helps train Kazuki in resisting mental magic, with little success. The only time he pulls it off is when Miyabi tries to seduce him by making them both naked in her Mental World, only for Kazuki to realize that she covered the critical parts with mosaic.
Volume 9
An example of Bathos. After a rather intense battle with Ikousai, who tried to let Susanoo possess her, both she and Kazuki end up being targeted by opposing factions, who are unsatisfied with the results of their duel. Kazuki then has to evacuate with Ikousai in tow, which turns out to be an awkward experience for the latter due to her lack of experience with men, to the point where she thinks she's been dirtied by a mere bridal carry.
Volume 14
It's somewhat amusing that the Final Boss, Lucifer, was killed off so easily by Kazuki's Kasane, which is an Awesome, but Impractical technique that saw little use for most of the series.
