Early in the series, Ryouta and Kuroha try to secure medicine to delay Kuroha's and Kana's deaths, but they were up against Saori, whom Kana foresaw that Ryouta and Kuroha would both die to. Despite Kuroha's letter to not save her, Ryouta successfully manages a fatal sneak attack on Saori and forces Saori to use her trump card to save herself and Kuroha. Coward or not, Ryouta has some gall to attack Saori despite how strong the Magicians said she was.
Later into the series, Kana has a premonition that Kazumi was going to die, with the exception being that this death was unchangeable because the plan had a Magic User whose clairvoyance is 100% accurate and would alter reality itself to ensure that the vision happens. Ryouta's response? He consults with his uncle and Kazumi to form a plan that could counter any situation this kind of Clairvoyant could cause, but hinged on the idea that Kazumi was going to be either the one who dies or aSecret-Keeperof some sort. Despite all possible hangups that could have gotten at least one person killed, not only does the plan succeed without a hitch, but NONE of the main cast get injured or die in the process (though Kotori does get stuck in a partial Funny Moment when she switches locations with a dog on a leash).
Murakami giving the girls a well-deserved What the Hell, Hero? when they fail to demonstrate their magic to his Agent Scully uncle. After all the free passes he's given them, it's so refreshing to see him rightly pissed off at those girls.
After Kotori nearly hatches into the Grane, Ichijiku dies and Valkyria blows up a city with antimatter, things are looking grim. Murakami thinks up a strategy to kill Valkyria: distract her with Kuroha while he sneaks up to her and slashes her throat with a knife, even though she'll probably retaliate and kill her. Unfortunately, she figures the plan out quickly, and is about to kill them,when suddenly, Kana appears, having recovered use of her body, and slashes out Valkyria's throat. Stone-cold awesomeness.
Kuroneko vs Valkyria. After Kuroha is stabbed by a knife, Murakami presses the top button on her harness, knowing that she had more power from Valkyria before it was sealed, and pressing the button will unlock them in the small chance she doesn't die. It succeeds, and also restores her memories as Kuroneko, helping her to remember everything about Ryouta. She then kisses him, saying she's loved him since they were kids. The ensuing fight and defeat of Valkyria is quite a sight.
The last page of chapter 147, where Kana and Mina stand with a nice hat and sunglasses, proudly announcing that they're coming to the trip to Ishigaki Island. It manages to be Awesome, Funny, and Heartwarming, considering what both Kana and her sister went through in their life. Really nails the point that, yep, they are sisters alright.
