Joel Ejorcadas and Marlon Pepito Jr. stayed for hours at the shrine dedicated to the victims of former president Rodrigo Duterte’s bloody drug war, with candles lit in memory of their murdered kin.

This was before [human] trafficking laws [in the Philippines],” says Oebanda-Pacis. “Girls [were] promised work and a good life in Manila [by traffickers],” then were forced into brothels and ...