They climb down

You follow them down the highway ramp and into the city. They stand at an intersection for a second, considering where to go, and then the athletic blond grabs a manhole cover.

"Down there!" She screams, as everyone around the moaning and grunting of the dead become louder. You hear your fellow zombies closing in, attracted to the same warm flesh that has brought you here, so you charge at your preys in a last-ditch effort to get laid.

Sadly, your momentum leads you directly towards the strong lady, and the large metal circle she wields like a shield.

You hear a crunch as your body slams into the manhole cover, and then your visions becomes blurry for a moment. The impact seems to have shaken her as well, but you can't take advantage of it since you are yourself dazed and lying on the ground.

By the time you shake your head and regain full consciousness, you can see the two women climbing down into the hole, and replacing the cover just as another zombie lunges towards it. The brain-dead stud fruitlessly claws at the closed sewer entrance for several minutes. Other living dead arrives as well, joining his efforts. They only stops when the residual heat and smell of the two live ones has fully dissipated, and then they are left dumb-founded as they do not remember why they were attacking a sewer grate.

You get up, frustrated, and then spots your reflection in the window of a nearby store. On top of not having had sex, your nose is now broken. It has not been a good day.