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I work in an office of 6 or 7 people a day. I absolutely like everyone and it is a really nice place (seriously). I want to stay here a long time and continue working with the same people. I have a coworker I get along with really well (despite our age gap) and we hit it off perfectly. He found out that I am an Excel and MS Office guru and I have been helping him with some special projects and he wants me to continue to help him. I love helping and have no problem with it except...
His breath, however, smells like a sewer. He smokes, possibly a lot (I don't keep track), so that might cause it.
I want to continue helping him and working with him, but I don't know how to handle the odor coming from his mouth if I have to sit next to him for extended periods of time.
How do I handle this so that I do not hurt his feelings, look snobby, and avoid anybody getting hurt or disgruntled?
Please note that this situation is not to the level of disciplinary or managerial action. This could easily apply to a minor habit of a coworker that is a pet peeve of another.