(Sorry I didn't make anything for a while, I've been pretty upset lately, don't worry, I'll make something else soon from this)
So... you live in the world of Left 4 Dead, specifically the second one. It's not all bad, all you really do is scavenge and shoot zombies, also being immune. You come across some other survivors eventually! The L4D2 ones, Ellis/my personal favorite, Rochelle, Nick, and Coach, so you decide to stick with them for a bit. After a bit of horde killing, you come across a Spitter... but... it didn't seem aggressive, it seemed pretty docile... also, it was more curved and had a more appealing form, it's chest was also bigger than average... however, it stared at you weirdly, with a strange gaze... almost lustful... so what do you do?