It’s hard to walk around Japan without coming across the cuddly characters of “Chiikawa,” the web manga by . They dangle from handbags, fill arcade claw machines and smile from Uniqlo T-shirts, making them among the most recognizable kawaii mascots of the current Reiwa Era.

It’s not surprising, then, that the franchise’s first feature-length film, “,” has been a cinematic smash success since arriving in theaters on July 24. It — the seventh-biggest first day in Japanese box-office history — before reaching ?2.24 billion by . “Mermaid Island” is already shaping up to be one of the summer’s biggest hits.

What many didn’t expect from an animated summer-vacation movie was something closer to Dostoevsky than Hello Kitty, with stunned social media users describing it as “.” They’re not entirely wrong.