The manga in question is called "MAGI - The Labyrinth of magic"
Is an Arabian Nights-themed Japanese manga written and illustrated by Shinobu Ohtaka.
<<Aladdin, the primary protagonist, is traveling a desert land, with a magic flute that summons a djinn named Ugo. The djinn has a huge and muscular body, but cannot remove his head from the flute, giving him a headless appearance and frequently causing even people he is trying to rescue to mistake him for a monster.
The two meet Alibaba, a seemingly greedy and aloof young man who is trying to get rich, and realizes that Ugo would be a powerful ally to explore a nearby treasure-filled dungeon. As they adventure together, they become true friends, along with Morgianna, a slave girl from a distant land that they free from her master.
The three encounter other djinn, and hints that they may be destined to decide who will rule the world.>>
The characters in the header that I made are: Ali Baba (Blonde guy) and Sinbad (Purple hair guy) SinbadxAli Baba is now my OTP XDD (I like others but this is the best for me 8D)
I highly reccomend it, only to read two volumes and I fell in love with it xD (At the moment, I read five volumes, which are the ones in Spanish xP