AskZeref

Appearance:
Despite being hundreds of years old, Zeref has the appearance of a young man. He wears open-collared red (black in the anime) and tan robes with gold trimmings, along with a large, flowing white toga draped across, and around, his torso. He has messy black hair, dark eyes, and abnormally sharp canines. He also wears a circle-shaped necklace.
When angered, Zeref's irises become red and gain a black ring around the pupil, giving him a much more menacing appearance.

Personality:
Zeref is said to have been the darkest, most evil Mage in the history of the Magic World, doing so by mastering the Black Arts and creating many demons, some of which still wreak havoc in the present.
In the modern era, Zeref seeks to isolate himself and is very calm, sincere, and self-loathing. He wishes to die to atone for all the sins he has committed, and may commit in the future. He is also somewhat emotionally fragile, as when he realizes that Natsu is not ready to kill him yet, he breaks down in tears. Zeref often commits atrocities with no prior incentive or knowledge.

In spite of all this, Zeref is very vindictive, and seeks to punish those who he believes to be evil. As a result of his immortal life, Zeref has developed a misanthropic loathing for humanity as a result of its repeated idiosyncrasies of hate, evil, and conflict he has witnessed over the years and the repetition of its mistakes over the ages.