Damn

Lei or ren. Cant remember.

*len
his twin sister (or maybe friend, it's not officially confirmed) is rin

Len is a clone of rin.

They are often regarded as siblings but are more of the same person than siblings

r/technicallythetruth
i'm talking about, like, canonically
even if vocaloid doesn't have lore, there's a bit of information regarding the vocaloids

That's what the Creator of them said.