Looking at the private parts is much more prohibited
14-1-2014 | IslamWeb
Question:
I am a twenty-year-old young man whom Allaah The Exalted Guided after a long journey of committing sins. I sincerely repented to Allaah The Exalted except for one and only thing of which I want to know whether it renders my repentance insincere or not. I still keep a porn photo on my computer of a foreign girl revealing her private parts, given that I have deleted all other photos except for this one so as to keep it fresh in my mind whenever I forget what the private parts look like. Is it permissible?
Answer:
All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His Slave and Messenger.
You should thank and praise Allaah The Exalted duly for Guiding you towards repentance of your sins. Scholars believed that the repentance of a sinner of some of his sins, and not all, is accepted as Imaam Ibn Taymiyyah 
clarified in his book Al-Fataawa. Moreover, you should fully intend not to repeat such a sin sincerely; for looking at women is impermissible, not to mention their private parts which is much more prohibited and a reason for you to think of committing what is forbidden. Allaah The Exalted Says (what means): {Tell the believing men to reduce [some] of their vision and guard their private parts. That is purer for them. Indeed, Allaah Is Acquainted with what they do.} [Quran 24:30]
Hence, you should delete this photo and utilize the computer in useful activities; for this technology is a blessing bestowed upon us by Allaah The Exalted and should be used in enhancing our submission and obedience towards Allaah The Exalted. Allaah The Exalted Says (what means): {Thus Does He Complete His favor upon you that you might submit [to Him].} [Quran 16:81]
Knowing what a woman’s private parts look like is not a valid reason under Sharee‘ah to do what you have done; for it is needless to look at and recognize woman’s private parts. Furthermore, you should ask Allaah The Exalted for forgiveness and carry out more and more righteous deeds; Allaah The Exalted Says (what means): {But whoever repents after his wrongdoing and reforms, indeed, Allaah Will Turn to him in forgiveness. Indeed, Allaah Is Forgiving and Merciful.} [Quran 5:39]
Moreover, dear questioner, you should seek marriage, make full use of your spare time in useful activities, adhere to performing prayers at the mosque, attend religious lessons and keep the company of righteous and pious Muslims.
Allaah Knows best.