Sweet Punishment: I'm the Guard's Personal Pet

Framed for embezzlement and tossed into Kokuyoku Prison, Hina Saotome is completely innocent, which would be bad enough on its own. The twist that makes things considerably worse: she's the only woman in a facility full of men. And the warden, Aki Myoujin, has it out for her specifically, for reasons he's not sharing. His idea of discipline doesn't exactly follow the rulebook, and the lines between punishment and something else entirely start blurring fast. Don't go in expecting a straightforward prison drama. this is a 13-episode ONA with short episodes and a very specific focus on power dynamics and forbidden tension between Hina and Aki. The drama is real though, and Hina's situation, wrongfully convicted, trapped, and emotionally cornered, gives the story more weight than you might expect from the premise. If you've watched something like Souryo to Majiwaru Shikiyoku no Yoru ni or 25-sai no Joshikousei and you're comfortable with that territory, this fits right alongside them. It's josei-coded, which means the emotional undercurrent and Hina's internal conflict actually get some attention rather than being an afterthought. Based on a web manga and produced by Magic Bus, the series keeps things compact and focused. If you want something short, intense, and unapologetically in the adult drama lane, this does exactly what it sets out to do.