I'm not sure how much value there is to being best girl in a dumpster fire manga, but if there's any girl out there eligible in this story it's only Yako as a no-brainer. But the downside is that being too good also means she's not really a match for a weak-willed dumpster fire manga protagonist. Which is why I'm rooting for Umimi instead. Yako deserves a better guy than Riku.
Yako's still too strong, so in addition to her inability to cook, she also cannot swim despite being the initiator of this entire beach arc happening. But I don't think that will stop her fans from supporting her. In fact, they'll probably love her more for these flaws so far. If she wasn't in love with Riku before, I think she is now. A girl like her wouldn't flash a guy she has no feelings for.
For a moment there I thought this entire sequence was just Umimi's nightmare, but it did happen after all. That close up of Yako on page 18 made me think it was Umimi, but the fang says it's Yako after all. Why did Riku get even more depressed? Because he got his D seen by a girl not named Shizuku? The male lead staying pathetic as usual...
Anyway, the uncomfortable implication that the would-be rapist is still out there freely plotting his next moves helps make sure this is never a comfy read like usual, even with a mostly wholesome chapter like this. A reminder that the trainwreck is chugging along right on track...