I am man living in USA and usually I put in my pocket Qur'an. Some time I need to go to the bathroom and for some reason I forget to take the Qur'an out of my pocket. I remember it only when I am already inside. What should I do? And how does the Muslim religion looks at it?

Praise be to Allah, the Lord of the World; and may His blessings and peace be upon our Prophet Muhammad and upon all his Family and Companions.

A Muslim is obliged to avoid any action that is contrary to the glorification of Allah and the greatness of His remembrance. So, he should spare no effort to glorify Allah and honour the remembrance of Allah. Allah Says (interpretation of meaning): {… And whosoever honours the Symbols of Allâh, then it is truly from the piety of the heart.} [22: 32].
Therefore, entering a bathroom or a toilet with the material that contains Allah's name or the like is actually an act of disrespect even if one does not intend so. It is narrated in a Hadith that the Prophet (Sallallahu Alaihi wa Sallam) used to remove his ring engraved with Muhammad Rasulullah whenever he went to the toilet. Though many scholars considered this Hadith weak the above verse proves the same meaning hence the Muslim scholars relied on it. Ikrimah reported that whenever Ibn Abbas (Radiya Allahu Anhu) went to the toilet he used to give me his ring. A Muslim should avoid taking any material that contains Allah's Name or His Dikr (remembrance) to impure places such as toilets. If one cannot do so or forgets to keep it outside and remembers before beginning to answer the call of nature then he should return back to put it outside. If he does not remember it except after beginning to answer the call of nature then he should cover it as reported from Ikrimah who said: "If one is compelled to enter the toilet with his ring that contain Allah's Dikr he should take it inside his palm and then hold it with his finger" [ Ibn Abu Shaibah ].
Allah knows best.