If you're looking for manga similar to 15 Years Old: Starting Today We'll Be Living Together, you might like these titles.
Hatsumi Narita lives in a typical company housing complex with her seemingly typical family, but the dramatic turn her life is about to take is anything but, well, typical. Her precocious younger sister Akane is way too popular with boys, her childhood friend Azusa, now a hunky male model, might want to ruin her life, her super-mean and very privileged neighbor Ryoki considers her his slave, and her dreamy older brother Shinogu might not be what he seems at all. What is a hapless heroine to do?
Uchiha Sasuke journeys to the Howling Wolf Village, where Itachi's eye medicine was produced.
In Fushimi, Kyoto, a jr. high school girl named Inari Fushimi has a crush on a boy, and acts a little foolish in trying to tell him her feelings. In a strange turn of events, Inari is able to change shape to the person she wants to be, and her love story in Kyoto takes many drastic turns for the better and worse!