I check his Bitcoin address, he received like $40 per week, 3 weeks already enough to pay the loan in full.
Doesn't that seem kind of predatory? I mean, I get it, free market, interest adds up, extensions taken... But for some reason I thought you were Muslim. This can't be halal.
If we're talking about halal and haram, lend someone with additional interest is already haram in the first place, no matter small or big the interest. It's become halal if the loan is interest free and the borrower give additional interest voluntary, not forced.