
Second Blue is a Japanese BL series about a book designer who reunites with a school crush. The main character is surprised to see a university friend at a client meeting. There was once a romantic spark, which vanished after one of them found a girlfriend. They've lost touch since then. After their unexpected reunion, the protagonist feels awkward about their history. As they collaborate on a project, their old feelings begin to return.
I liked the moody atmosphere in Second Blue. This dreamy love story captures the yearning and the tormented feelings quite well. In particular, the series shines during one of the flashbacks. Between the deep talks and the gorgeous ambiance, everything clicks into place. Despite showing some potential, the series didn't focus enough on the couple's romance. The story also became too angsty, and I lost interest by the end.
Second Blue Summary
Title:
セカンドブルー
Series Info:
Japan (2025)
Genre:
Office romance
About:
Second Blue is a sad & emotional BL drama.
Plot

Daichi is a book designer at Rise Inc. Books ' Editorial Design, where he creates covers and layouts for new titles. This job is a great fit because he's a lifelong reader. At home, he's surrounded by stacks of books in every room. Daichi even brings a novel to the meals so he can read while he eats. This habit follows him to his lunch breaks at work. One afternoon, Daichi leaves his book on an outdoor bench after finishing his meal. He realizes his mistake and rushes back to find it, but it's already gone.
Kousuke finds the book that Daichi left behind. He identifies the owner because Daichi uses a business card as a bookmark. Kousuke remembers him from their university days when they played in the same badminton club. Back then, Kousuke wore glasses and always had his nose to a book. They once spent a night together on campus, and a romantic spark flared during their precious bonding time. However, Kousuke later found a girlfriend, which led Daichi to quit the club. The two men haven't spoken a word to each other since that time.
At work, Daichi starts a new project for a photo book with Marufuji Publishing. He'll be designing the layout for an underwater photographer. Since his regular contact is going on maternity leave, he meets her replacement. Daichi is shocked to see Kousuke. This is their first meeting since university. Kousuke seems excited to reconnect, but Daichi feels awkward because of their history. Their colleagues only know that the two men went to the same school. No one suspects that there was ever anything more than a platonic friendship between them.
After Kousuke leaves, Daichi's colleagues start to gossip. They heard he used to date Rino, a culinary researcher with a large social media following. Her father is also a famous politician. Rino was Kousuke's girlfriend back in university, but the two are allegedly no longer together. When Daichi's coworkers ask him to confirm the rumour, he admits he doesn't know the truth. Deep down, Daichi has complicated feelings about Kousuke's current relationship status.
Daichi and Kousuke begin working together on the book design project. During one of their meetings, the power suddenly goes out, plunging the room into darkness. Kousuke is shocked and collapses to the floor, caught in a minor panic attack. Daichi immediately moves to comfort him. When the power comes back on, Kousuke recovers, though he feels slightly embarrassed by his reaction. This moment helps ease the tension between them. As they grow comfortable with each other again, their old feelings begin to resurface.
Second Blue Trailer
Second Blue Cast
Characters
Daichi
Koyo Tsutsumi (堤恒陽)

Daichi works as a book designer at Rise Inc. and spends his time surrounded by books. He even reads during his meals and lunch breaks because of his love for literature. When he runs into Kousuke at a meeting, Daichi feels uneasy about their past together. Daichi tries to stay focused on his work, but he gets distracted by his old feelings.
Koyo Tsutsumi

Koyo Tsutsumi (堤恒陽) is a Japanese actor. His first BL project is the 2025 short office drama, Second Blue.
Kousuke
Miki Hasegawa (長谷川幹)

Kousuke works at Marufuji Publishing and collaborates with Daichi on a photo book. Back in university, he spent his time in the badminton club and socializing with friends. Kousuke dated a girl named Rino years ago, which led to him and Daichi losing contact. Now that they have met again, he's excited to talk to Daichi and reconnect.
Miki Hasegawa

Miki Hasegawa (長谷川幹) is a Japanese actor. His first BL project is a leading role in the 2025 series, Second Blue.
Supporting Cast

Rino
Shion Tachibana (立花紫音)

Daichi's boss
Hiroaki Kawatsure (川連廣明)

Daichi's coworker
Miyu Hirooka (廣岡実夢)

Daichi's coworker
Kaori Yamashita (山下香織)

Kudou
Koike Mayuka (小池真優香)

Tokunaga
Masako Tokunaga (徳永真子)

Teramoto
Asami Rion (浅見りおん)

Kousuke's friend
Sho Minase (皆瀬翔)

Kousuke's friend
Yuumi Murakoso (村社侑美)

Kousuke's friend
Akari Kidouchi (城戸内アカリ)
Second Blue Review
Review
Drama Review Score: 6.7

Second Blue is a classic love story about second chances. Two guys had a school crush that never went anywhere. Now that they've reunited, those old feelings are coming back to haunt them. The plot sounds awfully familiar. You might have seen this exact scenario done better in dozens of BL dramas. While it's not original, Second Blue gets the vibes right. This series is moody as hell. It's full of yearning and unspoken feelings. The sexual tension makes you wonder who will make the first move and how his partner responds.
Midway through the story, Second Blue shows us a flashback. Both leads are resting side by side, with a dim lamp glowing between them. Then, the light changes into a cool shade of blue. Oh wow, it looks so pretty! This colour makes their expressions and eye contact look more intense. As the conversation drifts from casual talk to deeper topics, it genuinely feels like they're connecting. Hey, I can sense a romantic spark! Between the intimate writing and dreamy ambiance, this scene is easily my favourite part of the drama. If there's anything I'll remember about Second Blue, this moment will stick with me the most.
During that amazing flashback, I could picture Daichi and Kousuke as a couple. This BL drama had me believing love was in the air! Unfortunately, the magic only lasted for one moment. Like a puff of smoke, it was suddenly gone. That romantic spark just isn't there for the rest of the story. In the other scenes, the leads behave so awkwardly around each other. Hello, where's the chemistry!? The series hasn't developed the couple's relationship deeply enough. Give us more flashbacks to build up their past connection, or show us more warmth between them in the present.
Daichi seemed so sad at the start of the story. Kousuke is a more cheerful guy, so he has a positive influence on his friend. Look, Daichi is actually smiling for once! Unfortunately, Kousuke also becomes depressed in the second half of the story. Not you too! You were supposed to be the smiley one! Later in the drama, there's a lot of angst. The series focuses too much on the misery and not enough on the joy of romance. Yearning can be beautiful, but not when it drains the life out of everyone involved. It's hard to root for a couple when they make each other this unhappy.
Daichi's actor (Koyo Tsutsumi) is good at playing a brooding character. His stern expressions make you believe he's emotionally guarded around others. What a serious guy! When he finally cracks a smile, you appreciate the moment more because it's so rare. His co-star (Miki Hasegawa) has a bright smile that lights up the room. Early on, Kousuke brings a ray of sunshine to Daichi's gloomy world. However, the actor is slightly less persuasive during the emotional scenes. He seems more comfortable in a lighthearted role than at handling dramatic material.
Initially, I was invested in the couple's love story. By the end, I didn't care anymore. Between the constant angst and the lack of romance, I was mentally checked out. Even when Daichi confesses his feelings in the finale, it seems too intense. He talks about spending the rest of his life with Kousuke. Really!? But you basically pushed him away for the entire drama! Second Blue is disappointing because I see some hidden potential. I adore that special scene in the blue-lit room where everything clicks together. I just wish the rest of the story could have lived up to its best moment.
Summary
Moody story
Second Blue follows a familiar plot about reuniting with your school crush. I like the story's atmosphere with the yearning and unspoken feelings. However, everything becomes too angsty near the end.
Angsty romance
For one beautiful moment in a flashback, I sensed a romantic spark between the couple. That magic disappears way too fast. The couple seems awkward together in the other angsty scenes.
Decent acting
Daichi's actor (Koyo Tsutsumi) is great at playing the brooding type. His co-star (Miki Hasegawa) has a bright smile that lights up the room, but he seems less persuasive in emotional moments.
Happy ending
Second Blue has a happy ending where Daichi finally confesses his feelings. There's even a brief kiss. However, the final stretch was too angsty for me. I stopped caring about the couple by this point.
Dreamy artistry
The way this series uses light is gorgeous, especially that blue-lit room that made the romance feel so intimate. There's a dreamy atmosphere, even if the low-budget production is evident at times.
67%
Second Blue shows some potential, especially during a fantastic flashback where everything clicked into place. Sadly, the angsty story didn't develop the couple's romance deeply enough.
Second Blue Episodes
Episode Guide

- Start Date September 1, 2025
- End Date September 1, 2025
- Episodes 22 episodes
- Episode Length 3 minutes
Second Blue has a total of 22 episodes. Each episode is around 2 to 3 minutes long. It is a short BL drama, and you can finish the entire series in around 1 hour. Second Blue released all its episodes on September 1, 2025.
Second Blue Information
Links
- MyDramaList Second Blue MyDramaList
- Website Second Blue website
- YouTube Second Blue YouTube
Eggknock

Eggknock is a Japanese studio that has filmed various short dramas. Its BL portfolio includes Second Blue, a short series released in 2025.
Director
Yuki Uchida (内田佑季) is a Japanese director and writer. She has directed and written the 2025 short drama, Second Blue.