Zombie survival

When two 16 year olds are left alone (or so they thought) in a ZOMBIE APOCALYPSE, They set aside their "hatred" for each other and become very close. Then comes a threat. Then comes more threats. However, they realize that they are never safe. The only ones they can trust are are themselves. :( (Sucky summary, I promise the story is better) Rated m JUST IN CASE. Sexual themes.