I can say from experience that once you start looking it becomes very, very hard to stop. Things generally progress from there, just the way Satan wants them to. It leads to lust, possibly pornography, masturbation and eventually unfaithfulness to both God and your spouse. It is an addiction, very similar to a drug or alcohol addiction and once it has a hold on you, can be just as hard to get over.
I was exposed to pornography when I was 9. I found the magazine in a public restroom in the local Lowe’s Home Improvement store. I have had troubles ever since. It has only been recently that I have managed to kick the habits developed over the years and control, by the grace of God, the temptations.
These temptations if not controlled destroy lives, relationships and ultimately souls. It is this last that we should be most worried about. Pray that you may have the strength to overcome any temptation and God will give you the necessary graces to do so. Pray the Rosary and develop a relationship with her, you will need no other woman to look after.
If you have already started down this road(not directed at any particular individual), go to Confession, do penance and avoid the near occasions of sin. All of this will help to stay away from the snares and temptations of the evil one.