I once left the cockpit for a protracted period of time. The scenario was this:
A 2hr 50min one leg sector in an HS 748 on earlies.
The Captain, a young Australian (could only be) delighted in eating curries for dinner and then expecting one to join in his consummate exclamations of delight at his morning anal eructations. They were disgusting to a degree that was so poisonous that not even the use of oxygen could alleviate the ensuing nausea.
One sunny morning, just after we had cleaned up the aircraft; I announced to Skippie that I had to disappear. As I left the cockpit I scrunched two stink bombs on the floor behind his seat, went aft and told the antipodean air polluter, via the intercom, that I would not be back in the office until top of drop, some two hours plus latter.
I did relent somewhat on this time scale but the Old Cock Sparrow certainly never ate fire food again before flying with me.
Oh yes, in an effort to preserve the olfactory sanity of the front row passengers; I insisted to the Cabin Crew that the cockpit door should remain shut for the duration. The poor old chap never even got a coffee on that flight.
I have to say that Captain Kangaroo took the whole business in good part.
