Original Sin refers to man's natural tendency to sin. Why can't each man have a tendency towards particular sins?
If you're born to sin - you do have the tendency to sin. No matter what particular sin you'd tend to want to foster.
One can have the tendency to commit rape, thus we have serial rapists. One can have to the tendency to commit murder, thus we have serial murderers.
Some have the tendency to resolve matters or assert themselves through violence, thus we see assaults. Some have the tendency to want to have sex with anyone at every opportune time, thus we have fornicators and adulterers. Some have the tendency to have addictions. Some have the tendency to crave for material things.
Some have the tendency for sex with the same gender. Or to have sex with very young children. Or with animals. Or with a corpse. Or any other deviations one could think of.
It is a matter of self-discipline and control. To fight temptation. It is hard. Jesus Himself had said that - only few can walk the narrow road.
All of us - including Christians - will be battling temptation inside us for the rest of our lives. Having Jesus in our hearts, with the sincere desire to do what is righteous in the eyes of God, is what gives us the armor and the strength.
That's why you cling to Him, and never distance yourself from Him.....that's why having a personal relationship with Christ/God is so important. It is the key to our spiritual survival.