hand over fist

Adverb

idiomatic not-comparable

(idiomatic) Quickly or in great quantity, especially in reference to earning money.

Japanese Meaning

急速に、あるいは大量に（特に金銭が）増える / どんどん儲かる、急速に利益が上がる

After the update, the indie game sold copies hand over fist, bringing in more revenue than we'd imagined.

アップデート後、そのインディーゲームは短期間に大量の売り上げを記録し、想像以上の収益をもたらした。

Sense（1）

(idiomatic) Quickly or in great quantity, especially in reference to earning money.

He didn't earn much, but the company seemed to rake in money hand over fist.