A: (noun) A girl who frequently gives guys blow jobs. This is the literal meaning for penis-breath.
B: (adj) To have smelly breath so that people sitting around you back away from you
C: (noun) An out-of-the-blue insult, for example calling someone a bitch or a dickhead.
A: *sexual tone*
"Hey, how would you like to come to my place tonight?"
"Don't worry. I don't have penis-breath."
"His breath stinks! Let's just go now."
"Well there really is no point in sitting next to that penis-breath."
C: "Why didn't you come and meet me after school you penis-breath?"
"Oh sorry my bitchy English teacher gave me a detention."