What is it called when a victim's labor is demanded for repayment of an undefined loan?

The situation described, where a victim's labor is demanded to repay an undefined loan, is accurately termed Bonded Labor. This practice occurs when an individual is forced to work to repay a debt, often in terms that are not clearly defined, leaving them vulnerable and at the mercy of their employer.

In bonded labor, the terms of the loan and the conditions of labor are often exploitative, with the worker having little to no actual opportunity to repay the alleged debt due to high interest rates or other unfair conditions. This systemic abuse effectively traps individuals in a cycle of debt and servitude.

While the other terms also relate to labor and exploitation, they do not precisely capture the specific conditions associated with bonded labor. Therefore, Bonded Labor is the most fitting choice for the scenario where labor is coerced for the repayment of an undefined loan.