Seishun Buta Yarou wa Orusuban Imouto no Yume wo Minai

Sakuta's shut-in sister, Kaede, has been content always being at home after the bullying incident that put her there. Plus, that's where her favorite onii-chan is! Yet, slowly but surely, Kaede's feelings are beginning to change as she looks to the world beyond the four walls of her home.
(Source: Yen Press)