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...
I don't feel a damn thing, 
even though I've lost my hand...
لا أشعر بأي شيء البتّة رغم أنّني
...فقدتُ يدي
Ich spüre nicht mal etwas,
obwohl ich meine Hand verloren habe …
No siento nada
pese a haber perdido la mano…
No siento nada
pese a haber perdido la mano…
Même perdre ma main
ne me fait ni chaud ni froid.
Non provo un cazzo di niente,
neanche dopo aver perso la mano...
Até perdi minha mão,
e ainda não sinto nada...
Подумаешь, потерял руку.
Что мне с того?