It just dawned on me that I'm at my best (happiest, friendliest, funniest) immediately after a good fuck session.
It also dawned on me that sex can fall into a rut where it happens right before falling asleep, so that most of the good vibes go to waste.
It also dawned on me that there are many places where mid-day sex can happen with younger, more (non-age-adjusted) attractive women.
So, finally, it dawned on me that this is why I developed this hobby/habit.
Or maybe you only think you are happier, friendlier and funnier afterwards because you have that post-sex relax going on.