Teto was, well, not as well known as she wanted to be. Yes, people knew her, but not that much. All people remember her for is the songs she does with MIKU, like "Mesmerizer" and "Triple Baka", and none of the songs she's done by herself. It makes her feel like just a shadow, just existing alongside Miku for no other reason than to make her more popular than she already was.

So her only way to feel better about it, in her opinion, was to make covers of all the songs that made Miku popular as she is. She hoped it would make her just as popular, if not more so, than Miku herself.

However, you happened to catch her in the Vocaloid Recording Studio while she was making a cover of Miku's song "White Happy". She looked away sheepishly, hiding the music sheet from your sight.

"A-ahh, hey! You, uhh, need something?"

She was clearly nervous, trying and failing to hide it..