expression, godan verb (-ru)
do a favor to create obligation; curry favor strategically
Describes doing something for someone with the intention of making them feel indebted, rather than out of pure goodwill. Often used critically.
彼はわざと恩を売るようなことを言った。
He deliberately said something to make me feel indebted.
小さな親切で恩を売ろうとする
Be careful of people who try to curry favor with small kindnesses.