A lonely old man and woman have paired up in an old folks home. They get kinda close and decide to arrange a day when they are going to have sex. They choose a day when all of the other old timers are going on a day trip. The old man is excited because its the first sex hes had in years so he asks the woman upfront if theres anything she would like him to do.

She replies "Well i always liked it when a man would perform oral sex on me". So the man says, "Ok, that i can do" and down he goes only to return a few seconds later a heaving and barfing mess, when asked whats the matter he replies,
"I'm sorry darling i just can't do that, it smells funny!"

"Oh it must be the arthritis", the woman says, to which the man replies looking confused, "You can't get arthritis down there, and even if you could it wouldn't make that smell!"

"I know" the old woman replies, "the arthritis is in my shoulder, i can't wipe my arse!"