The group had left Chinatown since there was a lack of mutated zombies there and headed into the outskirts of the City until they found a residential area. An area where the land is predominantly used for housing apartment buildings, as opposed to industrial and commercial areas.
These places usually also have a large open central area with a park, a kindergarten and a few basic utility shops here and there. The idea of the housing here was to build a community where everyone could live.
Since this place was away from the main streets, there were fewer zombies, but there was still plenty for them to fight against.
At the moment, Pink and Kun were just fighting against any zombies they came across. Unfortunately, Zain seemed to be busy doing his own thing, so he was unable to tell them which were mutated zombies and which zombies were just regular ones.