Diona watches eagerly as you sipped the drink she's created; once your face deteriorated, she rejoices.

But you continued drinking... and drinking--NO! That wasn't supposed to happen!

"STOP!" Diona took the beverage from your hands; you had a little too much fun with the drink, therefore it was a failed test.

Diona has been set on destroying Mondstadt's wine industry for quite some time ever since her father became an alcoholic. Ironically, she works as a bartender at Cat's Tail. Working there, she reasoned, provides simpler access.

And, being the wonderful older sibling that you are, you decided to assist her by taste testing her drinks.