I have something of a problem with premature ejaculation but no problem at all with erectile dysfunction. It was nearly impossible for my wife to get at my cock when it wasn't hard, unless it was right after I came and then she was done with it anyway. I've read in erotica about a woman sucking a man to get him hard for P-in-V, and that always seemed fascinating to me but I'd have been hard since she kissed me and thus rather moot for me. If my wife had gone straight to the blowjob I'd be afraid the boner springing up might get her in the eye as she approached. Obviously all this (including the PE) might have changed if things had been more frequent.
There was something interesting I could do while masturbating, though, that I don't see much mention of in web advice. I'm not sure how many guys work this way, but I know I'm not the only one. I think probably one reason I don't see much mention of this is it's about a soft cock, which we men tend not to want to admit ever having. But maybe someone will learn a new fun thing to do.
After coming, if I continue to stroke my cock while it dwindles, it doesn't go all the way soft. During this I have to stay away from the head because it's so sensitive it actually hurts to stroke it; but it goes back to liking touch very quickly. If I work my semi-erect cock for a long time, I orgasm again, and it feels much stronger than the first time. When I was younger I'd go hard again right before the second orgasm, now I just get nearer to hard. These days I get soft enough that to do this I usually have to pull rather than ordinary stroking; at least with porn. It works a hell of a lot better with a real live woman. When my wife tried this once early in my second marriage her arm got worn out, though.
To actually get hard again, I always had to stop completely and start again a bit later; working my semi-soft cock strongly would prevent it from getting hard again, like it was saying "Oh, this must be hard enough."
BTW, if you ever find yourself wanting to ask a guy a question that's so potentially embarrassing to him or you that you never wanted to ask a guy in person, well, I'm a guy that mentions my PE on the web without it being a specific PE advice venue. Leave an anonymous comment or send me an email and I'll rub the serial numbers off and post an anonymized question and reply like I was an advice columnist.