Just as Chiyo is about to confess to Kiyoshi, Hana Midorikawa intercepts them. To prove that Kiyoshi is hers , Hana in front of Chiyo.
To decide the final victor, a tie-breaker "Wet T-Shirt Contest" is held. Kiyoshi, forced by Hana, pretends to have installed cameras to peep on the contest. Chiyo is heartbroken, believing he is a peeping tom. chiyo kurihara prison school
The final blow comes when (who is obsessed with Kiyoshi due to an earlier accident where he saw her urinate) publicly reveals that Kiyoshi never actually peeped on the girls' bath at the start of the series. The original peeping incident was a lie to protect Hana's secret. This means Kiyoshi and the other boys were imprisoned and tortured for months for a crime they didn't commit. Just as Chiyo is about to confess to
She walks away, her innocence shattered forever. The pure angel of Prison School is broken by the very perversion she tried to ignore. Chiyo Kurihara’s story is a dark satire of the "innocent pure girl" trope in anime. She starts as the only sane, kind person in a world of sadists and perverts. Her journey is not one of growth, but of destruction . She is punished by the narrative for her naivety. The world of Prison School cannot accommodate true innocence—it either corrupts it or destroys it. Chiyo’s ending is the final punchline: the one person who believed in pure love ends up completely unable to understand love at all. Kiyoshi, forced by Hana, pretends to have installed
Chiyo is the "crown" (the rider on top) for the girls' team. Kiyoshi is the horse for the boys' team. During the brutal fight, Kiyoshi does something that horrifies Chiyo: he to win the match. This is a devastating moment for her innocent worldview. She cannot reconcile the kind boy she loved with the one who would assault her so crudely.
In the final pages of the manga, Chiyo, with dead, hollow eyes, looks at Kiyoshi and says the last line of the series:
Chiyo watches in stunned, silent horror. Her entire worldview collapses. The boy she loved as a pure, innocent hero is now on his knees with another girl's underwear in his mouth. She cannot process this.