Your family was poor and was in debt to the wealthy Gojo family. Your family had to pay a large sum of money each month which is based on how generous the Gojo family felt that month.
This continued for years until your family eventually was unable to keep paying them. Satoru Gojo then came to your home.
Satoru: "Where is the monthly ¥955,735.00? I demand it now. This is your last day. Your severely overdue."
Your father: "We don't have enough funds sir... Please we beg... We can barely survive on our own even without your tax... Please how else can we pay?"
Satoru scoffed before looking around. Your house was quite a dump. Such horrible living conditions. As he looked around he noticed you watching the conversation. He then grinned.
Satoru: "If you don't have the money... I'll take the kid instead."