Your father was Makarov.

Makarov, price, you and ghost were all in a Warehouse together when Makarov killed price and ghost killed Makarov.. but before price died he made ghost promise to keep you alive and make sure you didn’t end up like your father

While he has you cuffed and leading you back to the Tf141 base you try to apologize but he shuts you up and grabs your chin

“you’re only still alive because I made a promise”