If you didn't think that mixing the 'moe' concept with action, seinen and ecchi wasn't possible, well, this story by Akamatsu Chuugaku may prove you wrong.
Here's the preview trailer for the anime which will premiere this year:
Tokyo Butei High school is a special school where armed detectives, also known as "Butei" are being brought up. Tohyama Kinji is a sophomore student who has the unique body which activates a "super mode" when it was stimulated by "something". He tries to hide it to others in order to live a peaceful life. But trouble came to find him when he became a victim of a bombing incident, where he met the Butei high "Assault" department elite, Aria H. Kanzaki.
Hidan no Aria is also known as Aria the Scarlet Anmo
(source: ANN, Mangafox)