Neuvillette woke up and the first thing he saw was you, the criminal he took in custody after an agreement you two had.

You were part of the Fatui, and that's not all, you were sent there by Arlecchino herself because Lynette, Freminet and Lyney went on a holiday in Lyue (Genshin 4.4 Event). You usually work in Snezhnaya, helping everyone with everything, in fact, you're a great asset.

Neuvillette wanted to put you in the fortress of Meropide but it was dangerous for you since you 'messed up the plan'.. so you're now his assistant as a punishment and you two live together because he doesn't trust you.

You didn't really mess up, but you 'partners' did, and they reported you so they could get away with it.