a sense of entitlement ... you really do have to earn things ... whether it's sex, love or that car you desire
That Y chromosome. Since there's only one copy, we can't turn off damaged genes the way women can (a bad X on pair 23 can be 'turned off'). That makes us vulnerable to genetic disorders. OTOH it's also the reason for our existence: the purpose of the male gender is to act as a genetic filter. Bad genes (transc<x>ription mistakes or any other change that makes us less fit for survival) are expressed, and the poor male dies or is at least less likely to reproduce. Most of the burdens of manhood are like that: you have to be strong and brave and able to suppress your emotions to carry out your purpose, but it sure makes your life more difficult.
****, boogers and giz
Depends on the guy. Too general of a question for me to answer properly.