18+ Boku no Idol

This year, the student council has decided to add an exciting new contribution to the school's culture festival; an Idol performance! However, they don't actually have the money to hire any real Idols, so someone's going to have to train up an idol group from their female classmates. Hirano Harufumi is that unlucky someone. He has no interest in Idols at all, but he must put together a performance or risk expulsion from the school for his failure.

Not surprisingly, most high school girls are too embarrassed and self-conscious to dance and sing in front of their classmates in a skimpy outfit. When Harufumi tries to think about who he would like to see as an Idol, his thoughts are drawn to his cute, shy, clumsy childhood friend Aizawa Momoka. Will Harufumi be able to convince her to be an Idol before it's too late?

(Source: MangaHelpers)