Well I mean he could have told her the truth, that everybody has bad breath in the morning and the cure is to brush your teeth. But then he wouldn't wake up every morning to a blowjob. So I mean what are you going to do.
Yuk, imagine getting a blowjob from someone with stinky bacteria breath. Your entire dick and balls would smell like that. Blowjob or not, brush your teeth or use some mouthwash!