Thank you for the explanation, Random duo.
Is that a common thing for a vtubers? To be honest I don't feel I don't understand much about vtubers at all. I thought they were just regular streamers that use an animated avatar instead of face cam.
They are just like most regular streamers with a 2D/3D avatar and some bonus lore to the character they use.
The voice clips/ voice dramas are more of an optional thing. A good few people do it, while others don't. From what I've seen (which admitably isn't a lot), most not all of those who do it are either big named VTubers or off-brand VTubers