Diary of a Step-Sister is an otome game by Voltage.

Your mother has remarried - and the person she's wedded to, is one of Japan's biggest millionaires!

You begin a new life in a new home, something completely different from yesterday.

You live there, together with...five step-brothers?!

"Do you understand? There are only men in this house."

Under the one roof, there will be several heart pounding stories occuring everyday!