1. The Title Song

The music for the fantasy TV series Game of thrones by the U.S. cable channel HBO is composed by Ramin Djawadi. The soundtrack is instrumental and features one major theme, the Main Title, which accompanies the series' title sequence

The music is noted for its popular main theme, which has been covered many times, and for its use of decidedly non-medieval renditions of songs from the series’ source novels by noted indie bands. 

Source: “There is only one god and his name is Death. And there is only one thing we say to Death: “Not today.” ― George R.R. Martin, A Game of Thrones

2. Lot of Sex

The sex is in the books so why not? It does not really break the pacing and there are not really that many, I would almost say its the one series where it does not feel so random as any other series, that just have them because they can. The way they have directed them is awesome and quite pleasing to the eyes. Which present generation enjoy seeing and later on discussing on it with friends and family. Don’t you?

Source: “There are no heroes...in life, the monsters win.” ― George R.R. Martin

3. Epic fantasy novel

The Strong knights, Huge well made Castles, Crazy war, Barbarians, strange gods like Lord of Light, made-up languages, and even Dragons who you see growing up. It’s a mix of all different emotions depicted beautifully.

Source: “Once you’ve accepted your flaws, no one can use them against you.” ― George R.R. Martin, A Game of Thrones

4. You don’t know what’s to come next

Central characters are killed now and then, weddings become blood beds, Psychopaths and bad guys develop consciences as time passes. The twists and turns of the plot keeps you hooked, and the developments that are impossible to anticipate give us a blood rush and leaves us thinking. The moment you think, what’s going to happen next the show proves you wrong.

Source: “The singers make much of kings who die valiantly in battle, but your life is worth more than a song.”

5. The good and the bad characters which you absolutely love

Let it be the worst Cersei lannister the sister and evil queen or the brother Jamie lannister father of the evil king Joffery Barratheon. The strong women like Daenerys Targaryen aS beautiful Khallisi, Innocent Sansa and Arya Stark and intelligent Margarey Tyrell. How can you forget the Tyrion lannister the most interesting and important. They are many more can't name them all. Much evil and less good but you fall in love with each one of them with every episode.

Source: “Most of us are not so strong. What is humor compared to a woman's love? What is duty against the feel of a newborn son in your arms? Or the memory of a brother's smile? Wind and words. We are only human, and the gods have fashioned us for love. That is our great glory and our great tragedy.” ― George R.R. Martin, A Game of Thrones