Morning Wood

I live alone so usually wake up all alone. However, this morning when I rolled over I bumped up against a nice hard cock! What is it about the mornings that cause guys to have morning wood? Is it because they have nasty dreams? Just curious...what causes this wonderful phenomenon? If anyone has insight as to the reason please let me know.

Needless to say...upon feeling that nice hard cock rubbing up against me, I proceeded to make it even harder until it wouldn't grow anymore. Then the guy woke up and we had wonderful sex.

Sorry ...no details this time...just want to know what causes those lovely morning erections!