Laylat Ragha'eb: Night of desires is a blessd night in which the reward is doubled for those who fast the during its day and revive its night by prayers, supplications and good deeds. And during this night, those who fast and ask for forgiveness have their needs and desires fulfilled, that is why the angels call it the night of desires "Laylat Ragha'eb."
Laylat al-Raghāʾib (Arabic: ليلة الرغائب) Is the first Thursday night of Rajab in every year, and it is a special night as the supplication and worship during it are greater than in the other nights as it is the night of the forgiveness of sins. The Prophet (Allah's prayers be upon him and his holy Household) said: "Do not miss the eve of the first Friday of Rajab, because it is the night the angels call ‘Laylatul Ragha’eb’: the Night of [the Granting of] Wishes. This is because, by the time the first third of the night has elapsed, there will not be a single angel still at large in the heavens, nor in any region of the earth. They will all be gathered together in the Ka’ba in Mecca and the area immediately surrounding it. Allah (The Almighty) will condescend to notice that they have assembled there, and He will say: “My angels, ask Me for whatever you wish!” Their response to this will be: “Our Lord, the request we wish to make is that You grant forgiveness to those who faithfully keep the fast in Rajab,” whereupon Allah (swt) will tell them: “That I have already done!”
Among the acts of laylat Ragha'eb:
The Messenger of Allah (Allah's prayers be upon him and his holy Household): "No one will go unrewarded if he fasts during the daytime on Thursday, the first Thursday in Rajab, then prays between Maghrib and Isha prayers, twelve rak'ah, and after finishing prays upon me seventy times, saying: "Allahumma Salli 'ala Mohammad wa 'ala Aalih" then prostrate and say: "Subbuh quddus Rab Al-Mala'ikati wal rouh" then lift his head and says: Rabbi ghfir wa irham wa tajawaz 'amma ta'lam, innaka anta Al-'aliyyi Al-a'dham." then prostrate again an repeat what he has said in the first one, then he may asks Allah his needs, and they will be fulfilled."
The Prophet (Allah's prayers be upon him and his holy Household) has said, these prayers are means of forgiveness and on the first night in our grave, God will send the reward off this prayer in the best and the most enlightened form. When it is inquired, it will reply, "my Beloved, glad tidings to you that you have found salvation from every hardship and horror." When it is asked, "who are you? I have not seen any one more beautiful than you, I haven't heard a word sweeter than yours, and a fragrance better than yours?", the reply is, "I am the prayer which you offered on the eve before the first Friday of the month of Rajab. I have come to you, to be your companion in this loneliness and to remove from you your fright and horror. Rest assured that my shelter will be with you until the blowing of the Horn of the Day of Judgment."