Futari de Obenkyo by Jingrock (Studying Together) is also part of the Shishunki wa Hatsujouki tankoubon. "Sunae is ready to become a woman, and she stays up late at night to study seduction. Then she invites Shin to help her with her homework..." - summary from baka-updates. Futari de Houkago (The Two of Us After School) is the sequel to the first story. Translated and edited by Rhapfan. Double Escape!! is a related story, featuring the same couple, translated and edited by Yoroshii. I've put them all conveniently in a package, so enjoy it.
Click to download Futari de Obenkyo.
