Sometimes I know how I’m going to rate an episode right at its start, especially with beach episodes, which can be half-assed chores. So as with most other episodes of its ilk, a “5” or average score is a good early baseline. From there, it’s up to the episode to convince us to either raise or lower that 5.
For the first three quarters of the episode, it was looking more like the latter: utterly boilerplate beach antics, complete with big bouncy boobs and male mischief. The only hint of originality was the fact that one notable character wasn’t wearing a swimsuit: Rurumo. Turns out she never bought one at the mall, possibly because she didn’t know she was supposed to.
That proves key, as Chiro (one of the fanservice centerpieces in shellkini-clad human form) manages to find her a swimsuit that just so happens to be “The Legendary Swimsuit” the president of the Occult Club is searching for. It imbues its wearer with romantic assertiveness, and when a witch dons it, it also augments strength and speed.
It comes up quick, but this is the turning point of the episode, because we know Rurumo harbors (and is trying to repress) feelings for Kouta, and we know Kouta is still invested in “reaching new levels.” This leads to Rurumo, under the influence of the swimsuit, making the first move on Kouta. Can Kouta resist? He can.
Watching a slightly sunburnt Rurumo doze on the train home, Kouta admits to a certain degree of regret he didn’t let Rurumo “have her way”, but considering how he’s treated her so far in the show, it’s really, as he said earlier, “better this way.” If and when Rurumo plants her first kiss on his lips, he’d rather she do it while of sound mind and frail body, not under a spell with him trapped under a concrete tripod.
After all that beach blandness, the episode finishes strong, reinforcing the show’s overarching premise that having Rurumo a persistent fixture in Kouta’s daily life continues to bring out the best in him. When push comes to shove, he can—and more to the point, wants to—set his hormones aside and do the right thing by her. And that’s what elevated this beach episode’s rating from the default of 5.