ka（カッ）
ka describes a sudden, sharp widening of the eyes, used to mark an instantaneous shift in emotion or focus.
ara-ara（アラアラ）
ara-ara describes a reaction of mild surprise, concern, or gentle disapproval expressed in a calm and composed manner.
kawaii（カワイイ）
kawaii describes something that is charming, adorable, or visually appealing in a soft, endearing way.