Kasumi Kishimoto is 15. Having arranged to stay with her aunt, she is surprised to learn that the other four people in the house are all male. <br /><br />The manga was originally 5 volumes long. Then it was reprinted in bunko 3 volumes (each bunko volume has more pages than the original volumes), and after that, it was reprinted again in 2 wideban volumes (even more pages per volume). Basically, the content and the length of the story is the same, they just come in different formats.