Decline Meltdown

A sudden accident, the death of my parents... Along with that, my happy childhood came to an end, and I thought I had lost everything... But who would have thought the real ordeal would come just three days later. Wait, Big Brother? You inherited the house and it collapsed within three days—your reverse scheming is absolutely terrifying... And on top of that, you abandoned me (8 years old) and my younger brother (3 years old) and ran off alone... Are you not a big brother but a demon? Faced with various circumstances surrounding our family's downfall, I resolved to protect my younger brother and survive with strength. However, it seems the world will not leave me alone. Having become a lodger at my uncle's house, I began conducting activities to gather information without the knowledge of adults. But then, I discover that an underground organization is searching for me... What on earth could this mean? (※The main story is complete. From now on, I plan to occasionally post side stories set after these events.)