When a guy with herpes kisses a girl and that same girl kisses a different guy, giving the new male herpes, making the two guys herpe bros.
“Yo I made out with Skylar two nights ago and woke up with a cold sore today.”
“Dudeeee no way. Her and I made out two months ago. She was pissed because I gave her herpes”
“Damn dude, she gave me YOUR herpes ?”
“Well I guess that makes us herpe bros”