Namaiki na Gal Ane wo Wakaraseru Hanashi

Sinopsis Namaiki na Gal Ane wo Wakaraseru Hanashi

She's a big sister with an attitude, and every time she opens her mouth, it's all just insults and negativity! However, her little brother has had enough, and he's got a plan to turn her into the cute, honest sister he knows she can be! To make it work, he'll first have to take her down a peg or two... (Source: Yen Press)