Aoi Kotonoha is one of the main characters in the Voiceroid series, a software application that allows users to synthesize speech in a variety of character voices. Aoi is known for her cheerful and energetic personality, often bringing a lively atmosphere to the series. She is the younger twin sister of Akane Kotonoha and is distinguishable by her short blue hair and lighthearted demeanor. Aoi plays a significant role in providing a youthful and vibrant voice, contributing to various narratives and projects within the Voiceroid community.