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...
Well, what are you waiting for? 
Get on your feet and come at me!
!حسناً، ماذا تنتظر؟ انهض وتعال إليّ
Hey, auf was wartest du noch?
Hoch mit dir und stell dich!
¿Qué esperas? ¡Levántate y pelea!
¿Qué esperas? ¡Levántate y pelea!
Allora, che aspetti?
Rimettiti in piedi e fatti sotto!
Tá esperando o quê?
Levanta daí e vem me encarar!