Furyouna Imouto No Shidou -rj01323679-

It looks like you’re referring to a specific adult visual novel or audio work (based on the “RJ” code from DLsite).
The complete title would typically be:

• Family Dynamics: The story explores the deep and sometimes troubled bonds within a family.
• Coming of Age: The little sister's journey into maturity is fraught with challenges that test her and those around her.
• Love and Acceptance: At its core, "Furyouna Imouto No Shidou -RJ01323679-" seeks to understand the various forms of love and the importance of acceptance.

Here's some general information:

The first few days were tough. Taro struggled to fit in, while Akane's enthusiasm seemed boundless. She would explore every nook and cranny of their new home, excitedly reporting her discoveries to Taro. But as the days turned into weeks, Taro began to notice changes in Akane. She was still eccentric, but there was a new sense of purpose to her actions. She started helping out around the house more, taking on tasks without being asked, and even began to help Taro with his struggles in school. Furyouna Imouto No Shidou -RJ01323679-