If you're looking for anime similar to Joshiochi! 2-kai kara Onna no Ko ga... Kudattekita, you might like these titles.
Aki lives a charmed life. Popular, athletic, and at the top of her class, she rules the school; and at home, her younger brother Sora caters to her every whim. However, her younger sister Nami doesn't have it so easy. The small-chested and sarcastic girl is in love with her best friend, who happens to be in love with Sora. Meanwhile, the slight and feminine Sora spends his evenings cooking and cleaning for the entire family while being bullied by Aki - and what's worse, he harbors a forbidden, deep-seated lust for the girl. Will Sora give into his desires, and will Nami ever win the heart of her best friend?
Father Yuri brings up the International Breast Research Society and their claims to be able to rid women of their ailments. Katja decides to investigate the rumors surrounding them further and learns that the society is not all what it seems.
Lately, shy Manami has been flirting outrageously and sparking vicious catfights! Afterwards, she remembers nothing. Can it be that another personality seethes beneath her own — a wild woman who'll do anything to find trouble?
Makoto and Yura Onoda are a newly married couple. Luckily for them, even though their marriage was arranged, they are deeply in love. However, even though they are both 25, neither of them have any ‘intimate’ experience, and consequently, they are equally as unsure and clumsy. With a little advice from Yura's friends and sister, this newly-wed couple will eventually get it right and explore the hardships of marriage, and the wonderful world of sex, even in daring places and awkward situations.