Yurivan Journal
Bad Thinking Diary: Read the Show Show GL Manhwa Online Free
Read Bad Thinking Diary online — Show Show's beloved Korean GL manhwa about Yuna and the best-friend kiss she can't stop thinking about. All 60 chapters, characters, content warnings, and where to read free.
Bad Thinking Diary (나쁜생각일기) by Show Show is one of the most-recommended Korean GL manhwa in WLW circles — the kind of slow-burn first-love story that gets passed between friends with the message 'just trust me.' It begins with one drunken kiss between best friends and unspools across years of confusion, desire, and self-discovery. Tender where it could have been crass, explicit where it earns it, this is the manhwa most often credited with making readers realize something about themselves.
What is Bad Thinking Diary?
Bad Thinking Diary is a long-running Korean GL manhwa by Show Show that originally serialized on Lezhin Comics' adult tier. It runs in full-color vertical-scroll webtoon format, is rated 19+ for explicit sexual content and emotional drama, and has built a steady international following despite slow English official translation. As of mid-2026, 60 translated chapters are available on Yurivan.
The series sits in the same emotional register as Pulse and What Does the Fox Say? — adult-feeling Korean GL that takes its protagonist's queerness seriously rather than treating it as a phase or a setup for fanservice. Where Bad Thinking Diary stands apart is its scope: it commits to following one girl from clueless teenager to adult woman, and that long-form patience is exactly what makes the explicit scenes hit when they finally arrive.
Story Overview
Yuna is a quiet, somewhat conflicted teenage girl with a tight circle of friends. One night, alcohol involved, she kisses her best friend. The kiss could be a mistake. It could be a confession. It could be the small accident that splits a life into a before and an after — which is exactly what it turns out to be.
From that opening beat, the manhwa stretches outward across years. We watch Yuna try to forget, try to be normal, try to want what she's supposed to want. We watch her notice things — a girl in class, a hand on her arm, the way a friend laughs at her jokes — and slowly stop being able to lie to herself. Show Show resists the urge to rush her: the diary in the title is real, and the bad thinking is the kind that compounds quietly until it has to come out.
The series escalates from teenage anxiety into adult intimacy as Yuna ages, and the pacing of that escalation is what fans cite most. The first explicit scene doesn't land until you've spent a long time inside her head wanting it to — and when it does, it reads as character payoff, not interruption.
Main Characters
- Yuna: The protagonist. The whole manhwa lives in her head. Quiet, observant, slow to commit to wanting things — which is what makes the slow-burn work. Her arc from confused teenager to woman who knows what she's reaching for is the spine of the series.
- Min-ji & the friend group: Yuna's best friend, the one whose kiss starts everything. The relationships within Yuna's friend circle become a slow-motion study of how queer crushes and friendships overlap, contradict, and sometimes have to be redrawn.
- Yuna's later partners: Bad Thinking Diary doesn't lock Yuna into a single endgame from page one. As the series moves into her young-adult years, she encounters women who change her — including some who help her finally name what she's been wanting all along.
Art Style & Format
Show Show's art is a defining part of the appeal: full-color, soft-painted, with a particular gift for the specific look of an embarrassed teenage face — the half-blink, the bitten lip, the pretend-casual glance that gives everything away. Backgrounds dissolve into mood lighting during emotional beats, and the explicit scenes are drawn with anatomy and intimacy in mind rather than checklist poses.
Format-wise, it's a vertical-scroll Korean webtoon designed for phone reading. Yurivan's continuous reader stitches the chapters into one strip so the long emotional builds Show Show writes don't get amputated by chapter breaks.
Why It's a Genre Standard
- Slow-burn done right: 100+ chapters of buildup is an obnoxious promise on most webtoons. Bad Thinking Diary uses every one of them. The first time something physical actually happens, you feel it like the reader has been holding a breath.
- Explicit scenes that earn their page count: Show Show treats sex as character work. Each scene shifts where the relationship is rather than just decorating it. That's what separates this manhwa from the 19+ tier's noisier titles.
- Real first-love texture: The bedroom-staring-at-the-ceiling chapters, the notebook entries, the rewriting of texts — Show Show captures what it actually feels like to be a closeted teenager replaying a single moment for months. Most GL skips this. This series lives in it.
- WLW canon: On Reddit, Goodreads, and WLW Twitter, this is one of the manhwa most cited as 'the one that made me realize.' That reputation is rare, and it sticks for a reason.
Read Bad Thinking Diary Online Free
Yurivan hosts the full 60 translated chapters of Bad Thinking Diary in our continuous vertical reader. No account, no paywall — just an age check, then the whole story scrolls. New chapters drop here as English translation lands.
Content Warnings
Bad Thinking Diary contains explicit sexual content, scenes involving intoxication, depictions of teenage emotional distress and confusion around sexuality, and adult relationship material as the timeline moves forward. There is no non-consent or violence; the discomfort the series produces is psychological — the unique ache of a closeted first-love that the protagonist isn't ready to name.
If you're sensitive to underage characters in any romantic context, note that the series begins in late high school before moving into adulthood. Explicit scenes are written with adult-aged characters.
Is Bad Thinking Diary Finished?
The Korean run of Bad Thinking Diary has progressed extensively, and a defined arc has been published. Yurivan currently mirrors 60 chapters in English; we'll continue to add chapters as new translations are released. We'll revise this guide and FAQ once the full run is available in English.
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Browse Manhwa →Similar Recommendations
If Bad Thinking Diary's slow-burn first-love texture clicks for you, these mature Korean and Chinese GL series share its DNA:
- Pulse (Ratana Satis). Two surgeons, one toxic-brilliant. Adult queer professionals dealing with disclosure and the cost of being closeted at the top of a career — the grown-up cousin to Bad Thinking Diary's young-adult arc. Read on Yurivan →
- What Does the Fox Say? (Team Gaji). Workplace GL manhwa with a complicated love rectangle and unapologetically lesbian leads. The genre's reigning adult drama. Read all 136 chapters on Yurivan. Read on Yurivan →
- Stop Fighting, Go to Bed (Kimguuk). New 2025 Korean GL about Heesoo's forbidden affair with another woman while her partner waits at home. Adult, explicit, ongoing — read all 50 chapters on Yurivan. Read on Yurivan →
- Tamen de Gushi (Tan Jiu). Chinese GL manhua. The wholesome opposite of Bad Thinking Diary — a 239-chapter slow-burn high-school romance with no explicit content. The other side of the GL coin. Read on Yurivan. Read on Yurivan →
For broader picks, our 14 best lesbian manhwa guide and 2026 GL manhwa roundup sit alongside this one.
Frequently Asked Questions
Common questions about Bad Thinking Diary answered below.
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