The way I see things, this anime doesn't have a decent enough storyline, mostly because I'm not grasping the whole "underwears protect your body" thing, which is basically the main point of the anime, that and underwears seen as a sex object. I could have given the storyline a 3.5 but since it has interesting ways to educate about developing female bodies and how it's important to choose the right underwear, i gave it a 4. In a way, this anime is actually very educational, ecchi, but at the same time educational. To be honest, I moderately like the opening, it's not my favorite, but it's catchy enough to not annoy the heck outta me! I like the characters, to be honest! Oh, if you're reading this, make sure you watch the series before reading this spoiler!!
** Spoiler Alert!!! click to hide or show**
I find Nayu very passionate about underwear, and I like that, only because passions draw in attention from people, which is why they watch series in the first place. Kiyono is viewed as a slut for some reason, but people already judge her just because of her actions and never actually understand why she behave that way and I hate people like that! First of all, I believe she's a girl who's following the wrong path of winning a guy she likes. her choice: seducing a man with lingerie is her philosophy of winning a man's heart. so you shouldn't judge a person by their action.
Animation is consistant and shows plenty of humor, at the same time, provides lots of fanservice even though the characters are only in 7th grade!! A series suggested to young developing girls...and maybe pedophiles. ^^ "
Character sources: http://en.wikipedia.org/wiki/Chu-bra
Nayu Hayama Voiced by: Minori Chihara
The protagonist of the story, who also acts as an 'underwear monitor'. She takes keen interest in underwear research. As a result, she is pretty shameless when it comes to her underwear, or anyone else's for that matter. Determined to inform people about the necessities of underwear, she forms the Underwear Appreciation Society.
Yako Jingūji Voiced by: Minako Kotobuki
A petite girl with a generally fierce composure. She prefers to keep a tough image, and has a hard time admitting embarrassing things.
Haruka Shiraishi Voiced by: Sayuri Yahagi
A busty girl and Yako's best friend. She often has trouble with boys because of them mocking her breasts. Presumed to be a lesbian with a crush on Nayu.
Hiroki Komachi Voiced by: Yuudai Satou
A boy who easily gets embarrassed at the sight of underwear. He has a one-sided rivalry with Nayu on school grades as he always ends up being second to her. He seems to have a small crush on her.
Kiyono Amahara Voiced by: Yōko Hikasa
A girl from a rich family who seems to be rather knowledgeable about the seedier side of underwear, and looks down upon Nayu for her naivety.
Tamaki Mizuno Voiced by: Sayaka Ohara
A teacher at Nayu's school who becomes the adviser of the Underwear Appreciation Society. She is generally nervous, but admires Nayu for giving her courage. She seems to have a crush on Keigo, who was her senpai in high school.
Keigo Hayama Voiced by: Takahiro Sakurai
Nayu's step-brother who has been looking after her since their parents died. He works as an underwear designer and often gets Nayu to test out his latest products.
I hope this review helps a bit. Thanks for reading!! ~_^