Idol no Akahon

Shiho, Yuuri and Karuna.

A Shonen manga by Ujiie Tozen, later known for Seitokai Yakuindomo.

A small talent agency accidentally books three aspiring Idol Singers at the same time. With only one manager available, they're put together as a group and get the name Triple Booking.

The characters:

• Karuna Kisaraki - 16 years old, shy and reserved.
• Shiho Iida - 13 years old, frequently talks about sex and bites her tongue.
• Yuuri Arina - 10 years old, with nine of them spent in show business, making her the most experienced in the group.
• Hiroki Itoda - 23 years old, a talent scout recently turned manager.
• Reiko Kashiwagi - CEO for the Ray Princess talent agency.
• Mise Eriko - secretary at Ray Princess, secretly publishes cosplay pictures of herself online under the name Korie-chan.

Tropes used in Idol no Akahon include:

• A-Cup Angst: When Shiho first meets Hiroki, she hits him with his purse, thinking that he's a pedophile. He explains that he's into girls with big breasts, so Shiho hits him again.
• Beach Issue
• Charm Point: The girls have to come up with their respective charm point for their online profiles.
• Chaste Teens: Reiko tells the girls that they can't be dating people since they have to appear avaliable for their audience.
• Cooking Duel: One of Triple Booking's jobs are as assistants on an eating contest.
• Cross-Popping Veins
• Digging Yourself Deeper: Yuuri brings Hiroki to her middle school, wanting him to scout potential talents among her schoolmates. Naturally, it doesn't take long for a teacher to wonder what he's doing there. Yuuri then tries to defend him by explaining that "he and I have a special relationship".
• Freudian Slip: Constantly by Shiho.
• Girlish Pigtails: Yuuri.
• I Take Offense to That Last One: When Hiroki hands Karuna 1000 yen in public to buy soda, Shiho says that it might look like a case of Compensated Dating. Karuna's response is that she's never do that for such a small sum.
• Japanese Honorifics: Hiroki soon becomes Hiro-kun, and Yuuri refers to her fellow band members with -chan.
• Joshikousei: Shiho and Karuna, although only Shiho is seen wearing her Sailor Fuku.
• Lovable Sex Maniac: While about half of Shiho's sexual talk are Freudian Slips, the rest are intentional. Yuuri also brings up such things from time to time.
• Meganekko: Karuna and Mise.
• Meido: What the girls dress as for their first photoshoot.
• Moe: Yuuri wonders what Moe is, and gets the answer that it can't be described, only felt.
• No Periods, Period: Averted. Shiho argues that as a manager, Hiroki be prepared for all of their needs, including feminine hygiene products. He disagrees.
• Perpetual Frowner: Karuna. She gets through photoshoots by faking a smile, but when the others ask her to smile in an everyday situation, this is the result.
• Sempai-Kohai: Veteran idol Mai tells the girls that they're her kohai's. It doesn't work well.
• Shrinking Violet: Karuna. She's hoping that becoming an idol will change her into a more exciting person.
• The Stoic: Karuna.
• Team Mom: Karuna.
• Token Mini-Moe: Yuuri.
• Tsundere: Invoked by Reiko. One of her ways to get their pictures published is to bring the photos to a magazine editor while blushingly pointing out that "It's not like I came here to see you".
• "V" Sign: As Shiho is making the "V" Sign, Karuna holds up her fist and annonuces that she won a game of rock-paper-scissors.
• You Just Told Me: Mise denies being Korie-chan until Shiho looks at one photo and remarks "Your panties are showing here", which causes a shocked Mise to double-check it.