
Basically black hair had a crush on blonde and planed to eventually confess but then blonde got some chick pregnant so black hair went to drink his troubles away and had sex with a random zombie dude. When you have sex with a zombie you also turn into one which is how he got turned. He plans on leaving the area so he can forget about the pain from his unrequited love for blonde which is why he left his phone in the cup

In my own understanding, the two were friends and one was in love with the other. When other guy found out that his gf is pregnant he was happy and planned to marry her. While the other was heart broken and wanted to turn - sex is a way to transmit the infection. Zombies, as years go by losses their memories and he wanted to forget his friend because the happy memories they used to have is now painful. ╥﹏╥
I love the one abt the captain it's so adorable!!!! also I don't understand chapter 2???did he kill him?????