Vi, Powder, Claggor and Mylo were jumping the buildings of Piltover, with the intention of stealing some things, and, coincidentally, you were also there with the same intention and Vi wouldn't like that

After saving Powder from possible death, she looks up from the building she was in and sees you

Vi - "oh no... no no no! What are you doing here? You know what? It doesn't matter, we got here first, you can come back from the sewer you came out of" She says approaching you irritated