Hatsune Mikuo (初音ミクオ)
A fanmade Vocaloid that is the male version of Vocaloid Hatsune Miku. Not much is known about Mikuo except that he inherits some of Miku's fanon traits, especially those regarding leeks. His voice is a masculinized version of Miku's voice samples.
Mikuo is often written as Miku's bigger brother than a twin. He is often illustrated with a body build like Kaito's, but illustration of Mikuo similar to Len (in shotacon sense) is not uncommon. He is said to be buddies with fellow derivatives Akaito and Meito.