While "Vocaloid" refers to the engine version of the same name, "Vocaloid(s)" can also apply directly to the mascot/avatar/personna of each "character" made for the Vocaloid engine. Not all Vocaloids have a physical form or a biography.
The term "Vocaloids" was a term fans of the software began using as a method of identificaying the mascots specifically for the Vocaloid software. While most packages adopt a character, not all opt for one and some remain avatarless. The mascot, or lack of one, is intended to act as a starting point of which the Producer can expand on and adapt their work to. The design itself can be adapted and altered to the Producers needs. Some mascots have a biography included with their package while others leave only vague hints or none at all. The mascots also form a starting point for the marketing of merchandise based on the Vocaloid.
The mascot has no effect on the software itself and is done purely for decorative reasons.
In Japan, the mascot is normally referred to as a "Vocaloid idol".
Akikoloid-chan is the mascot of the private use Vocaloid3 voicebank of the same name. Her design is controlled by Lawson and based on their mascot Akiko-chan.
Aoki Lapis is the mascot of the Vocaloid3 voicebank fo the same name. She is 15cm tall and based on a fairy and based on "light". Her race's concept as fairies is that they are a special race who can convert “songs” into “power”. They can only be seen by a subset of the human population. According to her developers, Aoki Lapis has no memory of who she is. She also has a elder sister named Merli.
Big Al is the mascot of the Vocaloid 2 voicebank of the same name. He is Sweet Ann's counterpart and was originally depicted in the same painted style of boxart as her. He is based on a Frankenstein's Monster.
Hatsune Miku is the mascot of the CV01 Vocaloid2 package, its Append, and future English version. She is based on a Japanese teenage school girl. CFM has stated that Hatsune Miku is "an android diva from in the near-future world where songs are lost".
Hiyama Kiyoteru is the mascot of the Vocaloid2 voicebank of the same name. He is a teacher at an elementary school, the same one that his counterpart Kaai Yuki attends. On the weekends he is in a band called Ice Mountain, details of which are written in a book of the same name.
Also in the book a bio was released;
Age = 22
Height = 5'9" / 179cm
Weight = 130lbs / 59 kg
Hiyama Kiyoteru's boxart illustration
Hiyama Kiyoteru as he appears in the TOKUMA MEDIA PLUS book "Ice Mountain"
Kaai Yuki is the mascot for the Vocaloid2 voicebank of the same name. She is based on an elementary school student. She attends the same school that her counterpart Hiyama Kiyoteru teaches at.
The male mascot of the CV02 package, Act2, its Append, and its future English version. Kagamine Len is based on a Japanese teenage school boy. He is Kagamine Rin's partner vocal.
The female mascot of the CV02 package, Act2, its Append and its future English version. Kagamine Rin is based on a Japanese teenage school girl. She is Kagamine Len's partner vocal.
Originally not intended to represent his vocals it has since become his avatar. Kaito is the mascot of the voicebank of the same name released for Vocaloid. He is also the mascot of the current Kaito V3 package. His counterpart is Meiko.
Kamui Gakupo is the mascot character of the Gackpoid package and its V3 updates. He has a samurai aesthetic about him but otherwise has no further details.
Leon has no avatar and is identified as "male" and a "soul singer". He is the mascot of the voicebank of the same name released for Vocaloid. He is Lola's counterpart.
Lola has no avatar and is identified as a "female" and a "Soul Singer".She is the mascot of the voicebank of the same name released for Vocaloid. She is Leon's counterpart.
Luo Tianyi is the mascot of the Vocaloid3 voicebank of the same name. According to her official profile, she is an angel who came to the human world with the task of bringing music to the world. She is very empathetic and while she does not communicate well with humans, she can connect to their feelings.
Mayu is a Vocaloid from Exit Tunes and the mascot of the voicebank of the same name. Mayu is intended to be a yandere influenced Vocaloid. Mayu is 15 years old and her birthday is the 6th of May.
Meiko has a female character on her boxart. Originally not intended to represent her vocals it has since become her avatar. She is the mascot of the voicebank of the same name released for Vocaloid. She is also mascot of the upcoming "Meiko Append" and "Meiko English" package. She is a counterpart to Kaito.
Merli is the mascot of the upcoming product of the same name. She is Aoki Lapis' elder sister. She is "dark" whereas Aoki Lapis is "light". The two are both sisters and enemies. Merli uses song to draw power from living things. Her personality is described as "strong-minded and tsundere; a charming mysterious girl who is innocent and changing the facial expression all the time. She's basically naive, but so innocent that she usually pretends to know everything ad hoc."
Miriam has no avatar, but a blurry photograph of Miriam Stockley is used as a reference for creating further avatars from. She is the mascot of the voicebank of the same name released in Vocaloid.
Nekomura Iroha is the mascot fo the Vocaloid 2 voicebank of the same name and was originally featured in the "Hello Kitty to Issho" game as one of the "Kittylers".
Oliver is the mascot character of the Vocaloid 3 voicebank of the same name. He is based on a Frankenstein monster, but has bandages instead of stitches like Big Al and Sweet Ann. He is 12 years old.
Ring Suzune is the mascot of the upcomingVocaloid3 vocal of the same name. She was described as "Light-hearted, doesn’t have high aspirations, but she’s hard-working."
SeeU is the mascot of the SV01 software package released for Vocaloid 3. SeeU was created to be a "cute and lively, yet mysterious 17 year-old girl." She is designed to look like a school girl.
SF-A2 miki is the mascot of the SF-A2 miki package released for Vocaloid2. According to the information that came from the 2012 redesign, miki was designed to look like she was made out of a inorganic material and was conceptualised as an android. Her body is designed to look like that of a child, but also give her the overall look of approx 14 years old. Though she is an android, she is covered in muscles made of various materials such as carbon nanotubes, but were made loose to give a mild deformed look about them.
Sweet Ann is the mascot of the product of the same name released for Vocaloid2. She has no offical design, however, her boxart is a mid-20th century poster-styled painting of a blond woman with curly hair and blue eyes. She is based on the "The Bride of Frankenstein". She is a counterpart to Big Al.
Her E-capsule release gave her the following details:
Tone Rion is the mascot of the Vocaloid3 voicebank of the same name. Her brief backstory states that she is 16 years old and was born in 2095, she is good at singing and dancing. Rion performs on the "Dear Stage" (ディアステージ) located in future Akihabara set 100 years from the current time.
Tonio is the mascot of the Vocaloid 2 voicebank of the same name. He is a classical/opera style singer. He has no offical avatar but fans often use his boxart as inspiration. He is a counterpart to Prima.
Ueki-loid is the mascot of the private use Vocaloid 3 voicebank of the same name. He was created using recordings of the voice of a dead singer, Hitoshi Ueki.
Utatane Piko is the mascot of the Vocaloid 2 voicebank of the same name. He is based on a teenage boy and bears a strong resemblance to his voice provider.
VY1 has a mascot, but it is not a person, unlike many other Vocaloid mascots. It is a hair pin and represents the Vocaloid2 package, and a more elaborate version for VY1v3. There is a deluxe version of the Vocaloid2 package, which is represneted by a fan.
VY2 has a mascot, but it is not a person, unlike many other Vocaloid mascots. It is a type of sword called a wakizashi. It is the mascot of the product of the same name for Vocaloid2 and will also likely represent upcoming VY2v3 package.
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