Showtime!: Uta no Onee-san datte Shitai

Shouji Fujimoto, a widowed single father who aspires to be a picture book author, encounters Minami Takasaki, a singing idol on the children's educational show O-nee-san to Uta-ou! (Let's Sing Along With Our Songstress!), outside work. As a television idol for children, Minami is lonely in her private life and is not allowed to fall in love. Any scandals are absolutely prohibited. Thus begins an adult love story with a songstress.

(Source: Anime News Network)

Note: The complete edition with explicit scenes was distributed on web via Comic Festa Anime Zone. The censored version was broadcasted on Tokyo MX and BS11.