The boy from Wolf Clan meets his brother whom he missed for such a long time while resting at countryside.

Original Webtoon:
Combined: Bomtoon
Main Story: Ridibooks, Lezhin, MrBlue
Side Story: Ridibooks, Lezhin, MrBlue

Official Translations:
S.Chinese: KuaiKan, AC.QQ, BiliBili
Japanese: Beltoon, Lezhin, cmoa, Renta, Booklive, Mecha Comic, Comico, Amazon Japan

Notes:
Brilliant Delusion Side Stories are Mature content and aren't included in the main story (except for Bomtoon; if your account is verified). Lezhin and Ridibooks have separate pages for them which consist of 12 chapters.