From an article elsewhere..."In 2005, Bain Capital, KKR & Co. and Vornado Realty Trust loaded Toys “R” Us up with debt to take it private." How does that work?

From an article elsewhere..."In 2005, Bain Capital, KKR & Co. and Vornado Realty Trust loaded Toys “R” Us up with debt to take it private." How does that work? Do any of these companies have a loss from all this debt they offloaded on Toys "R" Us? What would others lend so much money if this kind of things seems common?