Ima Sugu Oniichan ni Imouto da tte Iitai! ("I Want to Say to my Older Brother That I'm His Younger Sister Now!"), known as Imaimo for short, is a visual novel for PC and Playstation Vita developed by Fairys, with character designs by Akinashi Yuu. The manga adaption was illustrated by Oda Masaru.
When Mitani Rikuto's father remarries, Rikuto is given a cute step-sister who, for various reasons, must pretend that she is male.