Claire is eager to learn more about Shuuichi’s beast mode, but since it’s a hot summer day, she strips down to nothing before entering him again. This is a bit too scandalous for Shuuichi (more than a girl climbing inside him, apparently), so they compromise: she’ll wear her school swimsuit.
It’s clear Claire has fun teasing him with her killer body, but I’d hardly call this behavior sadistic—”teasing” is an adequate description of it, especially when she tickles him with his own hands. Also, she probably wouldn’t do it as much if Shuuichi didn’t have such reliably amusing reactions.
Their relationship has softened considerably since their first fateful encounter, and it’s likely due to the fact they’ve become one more than once now. It’s no longer antagonistic, nor does it smack as “we have no choice” reluctant cooperation. It’s starting to feel more like a partnership.
It’s a lot more like…two high school kids who never really fit in, hanging out and figuring this stuff out together. Neither is prepared for when Claire unzips the sleeve containing her sister’s uniform. It’s soaked with the stench of blood and the death of untold number of people.
Still, Shuuichi is desperate to learn why he came to be in this predicament and if it’s possible to reverse it, and when he’s one with Claire he feels a measure of her fear along with his own. That empathy-through-communion steels his normally timid nerves, and he resolves to help her find Elena, no matter what dangers or horrors come their way.
Claire admits she didn’t expect him to grow a pair, even calling his attitude “cool.” She clearly sees him as more than a tool to be used, just as he still notices the high school girl in her when she inspects her face in the fridge door. Heck, during their stakeout, she even admits unbidden that she’s still a virgin, erasing an potential rich avenue of Shuuichi-teasing.
Remaining out of sight and utilizing Shuuichi’s strong sense of smell, they eventually encounter Elena coming off a train. While Claire’s original plan was to talk to her sister, to try to understand why she killed their parents, but that goes out the window when she’s in their sights. Claire pulls Shuuichi’s big gun and prepares to shoot her, but Shuuichi stops her at the least minute, exerting control in a moment Claire is acting on instinct.
Then things get weird. Elena appears to be a beast like Shuuichi, but she can take numerous forms, and her human form evaporates into her smoke demon form as she gloms onto the back of Shuuichi like a predator about to make a kill. Only…she stops, and suddenly adopts a much meeker personality. Hanazawa Kana handles both the good and evil Elena quite ably, mirroring her dual performance of Nadeko in the Monogatari Series.
This suddenly human-again, polite, contrite Elena tells them that she understands how they feel and doesn’t mind if they want to kill her, but that they should go somewhere out of the way so as not to bother bystanders. Once in an isolated field, she bows her head and apologizes. To Claire and Shuuichi’s surprise, she believes she’s talking only to Shuuichi, and is apologizing for making him take that form.
When Claire lets out a yelp of surprise, however, It’s no more Miss Nice Elena. She transforms back into a smoke monster, sensing Claire inside Shuuichi and furious about it. She declares that Shuuichi’s insides “belong to her” and rips off Shuuichi’s head, exposing Claire to mortal danger.
This was all but unavoidable. Neither Shuuichi or Elena could avoid searching for answers, even if it meant getting into this latest life-threatening situation. Whether or however they manage to get out of it, the handsome “alien” with the coins only living things can see got it wrong: the inhabitants of Earth are hardly “all good people.”