Soaring on Light Wings: Back to the Top

Wearing a badminton shell and doing romance novels, I thought I could find a book about badminton, but I didn't expect it to be this one. This book is really the most outrageous book I think.

It's weird to read. I originally thought it was about badminton, and the details of the game were all mentioned in one stroke, but it turns out it's specifically about romance.

What kind of brother is this? It's too outrageous. His sister is being pinched and yet she's helping others?