Elderly couples are usually depicted as cute, amusing, and nonsexual. When elderly people do have sex or are even just physically intimate, it's most commonly depicted as awkward or disgusting. If another character stumbles upon them (or even hears about it), they might react with disgust, claims of mental scarring, flee in terror, and so on. The couple might fulfill elderly stereotypes during the act, such as crying out "Oh, my hip!", needing to take medication, or acting confused or oblivious to social conventions. One possible contributor is Parental Sexuality Squick - the thought that "these people are old enough to be my parents (or grandparents)!" Compare Dirty Old Man, Dirty Old Woman. Most commonly averted when the elderly character is particularly attractive. A spinoff from this article. Need examples and aversions/subversions - but please avoid examples already covered by Parental Sexuality Squick. Avoid examples where some viewers might find it disgusting but the work does not clearly treat it as such. No Real Life Examples.
Hello, Unknown Troper. You'll need to get known to lend a hand here.