Hadrat Anas ibn Malik (r.a.), the servant of the Messenger of Allah (saws) narrated: ‘The Messenger of Allah (saws) said, "Verily, Allah is more pleased with the repentance of His slave than a person who has lost his camel in a waterless desert carrying his provision of food and drink. He, having lost all hopes (to get his camel and provisions back), lies down in shade and is disappointed about his (lost) camel; when all of a sudden he finds that camel standing before him. He takes hold of its reins and then out of boundless joy blurts out: 'O Allah, You are my slave and I am Your lord. He commits this mistake out of extreme joy."’
Related by Muslim. quoted from Riyad-us-Saliheen (Hadith # 15)
Nothing pleases Allah Subhanah more than a person who has transgressed the prescribed limits of Allah, and that person realizing his error turns unto his Lord and Creator in ‘taubah’, and seeks sincere forgiveness for his sins.
In another narration, the Messenger of Allah (saws) said: ‘All of the children of Adam are sinners, and the best (or most loved by Allah) of those sinners are those who constantly seek repentance.’
Regardless of the quantity or the quality of the sins one might have committed in one’s past, if one turns back unto their Lord Most Merciful and seeks sincere repentance, Allah Subhanah has promised to forgive all the sins of His repentant slaves.