For half a second, it was unclear if the interview was veering off course. Ben's voice (those interviewed requested anonymity) suddenly became warm and persuasive. "I need a girlfriend that I can trust. Like, I need you. Can you be my girlfriend?" The man was explaining how, from a working-class neighborhood in Lagos, he subtly manages to win over the hearts of his "clients" – as Nigerian scammers call their victims – thousands of kilometers away.

Ben used to repair generators for a living. But since his income was too low, he turned to romance scams two years ago – one of the most widespread online frauds in Nigeria. "When I wake up in the morning, I try to see that you're up, check you over, see how you're doing here, I get to know everything about you," he continued, sitting on a plastic chair amid a maze of metal shacks. In the stifling heat, two men lay on the ground less than a meter away. The most important thing, Ben went on, unfazed, is to "build trust."

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