E.L.V.N or ELEVEN (イレヴン), is a two-person unit which mainly does rock songs. They have very little number of works.
They are: Yu-Ki (ユーキ) who is responsible for the lyrics, composition, Vocaloid editing, bass, engineering, movie and artwork compilation. YO (ヨー) who does the lead guitar and also helps with the composition.
E.L.V.N began as an utaite solo of Yu-Ki where he did song covers. He was joined by YO and formed a duo. Their first original composition was sung by Kagamine Rin and reached 100k+ views. However, it was not until the dawn of their video Kowase Kowase which made people notice them; it reached 200k+ views. Yu-Ki still do song covers, nonetheless.
Their song PVs are usually a montage of stock videos and different artworks by various artists.
E.L.V.N is fluent in speaking English as one can observe in their YouTube comments.