Hasan

Hasan is apparently Humza's younger brother in the series. Despite never being mentioned before, he actually made an appearance in the 4th episode. He appeared to help Humza fight Asif and his gang. After that, he isn't mentioned at all. He made a short appearance at the beginning of 5, calling to Humza.

He was confronted by one of Asif's gang members, and was nearly stabbed, but Humza stopped the knife and saved him.

He doesn't exist in the rest of the series, seemingly. Humza doesn't mention him, either.