niya-niya（ニヤニヤ）
niya-niya describes a sly, smug, or suggestive grin that continues over time.
niko-niko（ニコニコ）
niko-niko describes a state of smiling cheerfully and continuously.
Feel Japanese sound expressions, not just read them.
niya-niya describes a sly, smug, or suggestive grin that continues over time.
niko-niko describes a state of smiling cheerfully and continuously.