地上最強の弟!?

From Author Wars - https://authorwars.com/books/di-shang-zui-qiang-nodi-2462165.html

Overview:

Title: 地上最強の弟!?
Author: 藤孝剛志
Year: 2013
Type: Novels
Series: 姉ちゃんは中二病 / My Big Sister Lives in a Fantasy World
Number in Series: 1

Variant Titles:

2016. The World's Strongest Little Brother

Genres/Themes:

young-adult fantasy