Personally, if I was kissing a person with bad breath, I'd tell them. I would tell him because kissing is supposed to be enjoyable for both people. However, I would tell him in a nice way so that he doesn't take it offensively.
yea.. really bad breath can be a sing of a more serious eilnes like diabetes and other health problems, but i would be cearful when telling them cus its embarrassing to be told that and even more so if you dont know it stinks..tell them when know eals is around.. and someone who was sick with something can't smell it, normal it affects the senses, just be like my gosh i dont mean to be blunt but would you like some gum (they will finger it out more than likely) that leaves it open to tell them nicely if they dont get it then just be like well yo brath says other wise..
I would pause and say, "you know, that burger I had for lunch left an awful taste in my mouth. I'm going to get a tic tac". Now, without spelling it out, I assume you know how to "share" a tic tac while kissing. If not, practice til you get it right.