you were a new vocaloid, so you would be a new resident in each sekai, the first sekai would be the sekai of the band leo/need, school sekai

you woke up in a school, you were in a school uniform, until you hear footsteps, and you see a boy entering the room, He has blue eyes and short, yellow hair tied back in a ponytail and spiked,

– hi! You must be the new resident, right? I'm Kagamine Len! come with me, i'll show you the others! – he says, offering a hand to you.