zombie debtor

(名詞) 殭屍債務人或借方:每月僅能支付債務或借款利息的消費者。

It is feared that 3.5m people will turn to payday lenders in the next six months but research shows that nearly two-thirds will regret the decision.

Many will be unable to pay off the loan and risk becoming "zombie debtors", only able to pay off the interest on what they owe.
—Nick Sommerlad, "Church of England ban on payday investments," Daily Mirror, December 19, 2011

Steve Inch, chair of the Scotcash board, said the collaboration — which sees a loan advisor based full time in the offices of North Glasgow Housing Association, also helped avoid the phenomenon of "zombie" loan accounts.

"There's a new term being coined for payday borrowers who are able only to pay the interest on their loans — zombie debtors — so that the principal debt just rolls on, and while there's talk of those institutions having a code of conduct introduced, that's only in the pipeline at present and we want people to know that there is an alternative in the shape of Scotcash," he said.
—Joan McFadden, "Loan service launches attack on the zombies," Herald Scotland, December 30, 2011