Yutaka Horiuchi was literally on top of the world. A popular idol, she was beloved by countless fans, and was the darling of the entertainment scene, where she was regularly sought-out for various events and projects. However behind her bright and friendly public persona lurked a deeply cynical young woman with a huge chip on her shoulder, and whose prime motivation was the accumulation of money and fame, in that order.
When her management suddenly saddles her with a radio show, she's suitably disapointed because the pay wasn't that good to begin with. But when a food poisoning-related incident nearly dooms the show before it starts (and forces Yutaka to make a prolonged stay in the ladies' room), the production staff somehow manage to salvage situation by using a chance discovery... That one of their assistants, Harumi Tanaka, shared the same voice as her! Yutaka wasn't pleased of course, and then promptly quit. It was just one dinky radio program, after all. She had other jobs she could turn to anyway...
And then everything suddenly came tumbling down.
The president of her talent firm skips town, and what's more, leaves Yutaka saddled with all of the company's debt. With her reputation ruined, all she had left was the same radio show she so casually disregarded, but this time around, she had Harumi to help her through this low spot in her career. Can she ever go back to being a top idol though just through the show? Yutaka wants to try anyway.
Written and drawn by Keiji Watarai, O/A (オー・エー) was serialized in Young Ace magazine from November 2009 to September 2012. The manga is considered complete, with seven compiled volumes released. A radio drama based on it also aired in 2011 on True Comic Weekly+ Kai (真・週刊コミックTV＋版).
- The Ace: Yutaka's elder sister Sayaka, who was smart, charismatic, and easily mastered anything she got interested in, but never enough where she'd stand out and be actually recognized for what she could do. It was her casual attitude to this that angered Yutaka, as she felt it belittled her own achievements, enough so that she moved out to Tokyo just to make a point. However this is shown to be subverted later on, where Sayaka's ace traits are shown in a less positive light — as Kisaragi notes, because Sayaka could do everything, she was unable to be attached to anything or anyone, something that Sayaka herself admits to Harumi later on.Sayaka (with a downcast look): ... I'm extremely glad that Yu-chan didn't become someone like me.
- Animal Motifs: Much to her chagrin, Yutaka is often associated to... a hippo.
- Beneath the Mask:
- Behind her cheerful public persona, Yutaka is revealed to be a cynical money-grubber who took her idol work very seriously. In the wake of her fall from grace, her greedy side had mostly disappeared, leaving behind the cynic who still takes any work she can get seriously.
- Miho never fails to put down and belittle Yutaka whenever they run into each other. However this condescending attitude hides a very very devoted fangirl, who on some level still believes that Yutaka will be able to rise above the rut she's fallen into.
- Berserk Button: Showing a lack of ambition is sure to set off Yutaka, especially when the person in question actually has the skills to suceed or excel at whatever they're doing. It causes her to blow up on Harumi when the latter seems mostly fine with her very awkward stand-up routine, and was the primary case of her estrangement with her older sister Sayaka (who was an extremely gifted person who could literally do anything, and yet was just letting her talents go to waste).
- Blinding Bangs: Tsuda, the script writer for O/A, has these as a defining feature.
- Break the Haughty: Chapter 3 and a good bit of chapter 4 were this to Yutaka, where she literally witnesses her idol career fall apart around her.
- Career-Ending Injury: Prior to becoming an idol, Miho was a national-level baseball player, and many predicted that she would go on to represent the country for the Olympics. However a shoulder injury permanently ended that dream for her.
- Chekhov's Gunman: Deepthroat, one of the fans that sent in fanmail in chapter 7, makes an actual personal appearance in chapter 27, and yes, he's an actual submariner — in fact, he's the captain of a US Navy nuclear attack submarine.
- Cool Big Sis: Miho to her younger brother and sister.
- Cringe Comedy: Not intentional, but Harumi's stand-up routine during the amateurs event couldn't be seen as anything but this. It was so awkward that Yutaka (who was secretly watching with Ootsuka in the audience) could barely watch. Ironically, Harumi is actually much funnier while she's on-air, likely due to the fact that she can't actually see the people she's performing to.
- The Determinator: While Yutaka's always been serious about her work as an idol, this aspect of her only gets amplified post scandal, where absolutely nothing will stop her from getting her assigned work done, no matter how ridiculous it is. Often played for laughs such as in Chapter 26, where she has to run a hundred-kilometer route, just to hand-deliver copies of her new single to listeners of the O/A radio show. Even through the rain or up a mountain during a blinding blizzard or during live-fire exercises of the JSSDF.
- Dynamic Entry: Yutaka at the end of the first chapter, via knee to Harumi's face.
- Fangirl: As the contents of her room show, Miho is a massive fan of Yutaka, to the point where she can perform a routine from Yutaka's early career perfectly.
- Fleeting Passionate Hobbies: One of the things that galled Yutaka about her sister was how she kept on flitting from one interest to another when she could have arguably become the best at any of them had she focused on just a single one.
- Forgotten First Meeting: Yutaka has long forgotten that she had actually met Miho before, during an audition when they were both amateurs. Ironically it was Yutaka's irritated outburst during that meeting that actually shaped Miho's idol persona.
- Friendless Background: One of the things that Yutaka had to forego in her quest for fame was any kind of friendship.
- Hidden Depths: Miho was Yutaka's greatest rival at the height of her popularity... But she's also secretly Yutaka's biggest fan.
- It Amused Me: Most of the ideas that Radio Ace's producer Taki comes up with for segments in O/A boil down to whatever she thought was interesting at the time.
- Limited Wardrobe: Harumi is always seen wearing her track jersey and pants.
- Major Injury Underreaction: Yutaka is actually hit by a car in Chapter 4(actually the taxi her manager hired to bring them to the radio studio), but she shrugs it off, all to get to her show.Taxi Driver: Is it really okay not to go to the hospital?!?
- Taki, the producer of Radio Ace.
- Ootsuka, Yutaka's long-suffering talent manager and, later on, boss.
- Miho while at home, aka her "real" and non-idol persona.
- Non-Promotion: Yutaka's manager Ootsuka becomes President Ootsuka, when she starts up her own talent agency to continue managing Yutaka... Except this has been what she's always been doing anyway. The only thing that changed really was her job title, but that's it.
- The Rival: Miho Kaieda, to Yutaka, though Yutaka treats her as an annoyance most of the time. However, as many entries on this page note, she's not simply Yutaka's rival — she's also Yutaka's biggest fan.
- Tsundere: Yutaka, in a non-romantic manner, whenever she makes an excuse to check on whatever it is Harumi is doing. She even gives the classic tsundere line while she and Ootsuka are heading to the theater where Harumi will try her stand-up routine at.Yutaka : It... It's not like I came to cheer her on or anything!
- You Are Better Than You Think You Are: Yutaka doesn't consider herself a good person, even in the wake of the scandal that mostly killed off her reputation as an idol. Harumi doesn't agree.
- Waiting for a Break: Harumi wants to be a comedian (and in Chapter 9 is actually shown doing stand-up comedy at an amateur event) but apart from her part in the O/A radio show, her "real" job is delivering newspapers in the morning.