[Barmixer]

At my age I can no longer get a hard-on. If I take a viagra, I get semi hard. I still enjoy eating my wife's pussy, and she feels bad that I can't cum. I have read many articles about prostrate massage. I want to send her a link to an article, but am not sure how she would react.
She does not like me to play with her ass, but will finger me a little in the shower.

My question is - does masasging the prostrate cause an erection, enough that I can jerk off and cum as she does this.

Ideally, I would love her to take it in her mouth as I cum, or blow it in her face. Does anyone have advice as to positions, etc?