While some in South Korea have been boycotting Japan, they seem to draw a line at financial products that generate high returns.

While many Koreans have ceased buying everything from beer to cars to clothing from Japan, and have canceled trips there amid an ongoing trade spat and disagreements over historical issues, they have flocked to the nation's real estate investment trusts, or REITs.

Korean investors' holdings of Japanese REIT funds have quintupled from the start of the year to about 291 billion won ($248 million), according to data from investment information provider KG Zeroin Co. They've bought a net 60 billion won this month, which is set to log the biggest monthly inflow this year.