Sanrio Co Ltd, the parent company of Hello Kitty, saw its shares plunge as much as 18% on Monday, marking the largest single-day drop since May 2014. The sharp decline followed the release of the company's first-quarter financial results, which fell short of market expectations.

For the first quarter, Sanrio reported an operating profit of 22.4 billion yen, below the consensus estimate of 23.4 billion yen. Analysts at Sumitomo Mitsui DS Asset Management noted in a research report that the earnings report was lackluster, with no standout positive surprises to drive investor sentiment.