Do you know this manga?

It was about an old man who got told that he would die and wouldn't be able to get it up if he doesn't sleep with the person who is destined to save him. I remember vaguely that the old man was a lady killer but couldn't get hard anymore the manga/manhwa had a lot of sex scenes. One particularly where the old man had a road accident with a a young man and he gets hard because of him and his hearts beats really hard and later he imagines himself having sex with him although the old man is not gay, anybody knows it?