[Frailty]

Originally Posted by Kyero Fox

Spoiler for huh?:

How do you know it's him?

kind of obvious really
plus there's a caption that says ""that" person from hueco mundo"

is there any other person who can contact Soul Society from Hueco Mundo other than Urahara?
the only others that are there are Uryuu, Chad, Inoue and Nel. Urahara's your best bet