The person hiding in the mirror was Illuso from the Hitman Team. Fugo ends up being dragged into the mirror by Illuso's Stand, Mirrorman. Fugo then summons his own Stand, Purple Smoke. Despite Giorno wanting to find Fugo, Abbacchio decides to go look for the key, since that was their mission. However, once Abbacchio finds the key, he also gets dragged into the mirror world...
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¿Qué vinieron a buscar?
¿Qué vinisteis a buscar?
Qu’êtes-vous venus chercher,
alors ?
Che siete venuti a cercare qui?
O que vocês estão procurando aqui?
Что вы разыскиваете в Помпеях?