Talk:Incubus/@comment-45424649-20200707193354/@comment-10429980-20200715164544

On that the first line of what Zel quoted is relevant, namely "Just like monsters, their appearance stops aging at a certain stage. It could be as a boy, as a young man, or as a mature man."

So the difference is that the age you end up looking like may not necessarily be a "prime of life" age, i.e. that there exists incubi who do end up looking elderly. Though I'd wager that these incubi who look like "grandfathers" would typically be of the virile and charismatic "silver fox" variety rather than a frail elderly. I'd also wager that the typical incubus does simply stay in the "prime of life" to the day they die just like their wife, it's just that her own tastes can alter this a bit.