Not much is known about Arobynn's early history, other than that he owned an estate in Terrasen near a river 10 years ago.
Arobynn convenes his assassins in a meeting to notify them of the death of his second-in-command, Ben. Arobynn, although clearly disconcerted about the death of one of his assassins, maintains a cool demeanor. He prevents Sam Cortland and Celaena Sardothien from attacking each other during the meeting and has them—a few months later—meet with the pirate lord for reparations for the death of Ben. In the meeting, Sam and Celaena discover that Arobynn arranged a slave trade with Rolfe, the leading pirate lord.
However, he later betrays her, putting a (unbeknownst to him) fake Wyrdstone ring on Aelin's finger, in an attempt to use her to take control of Terrasen. He sends her away and is later killed by Lysandra in his sleep, as Aelin realises he can't be trusted.
Arobynn is seen in a flashback from Elena, in which he is shown waking from his sleep due to Elena's compulsion and riding to find Aelin. He finds her, picks her up and rides home.
Personality and traits
Aelin remembers Arobynn as a strict and unforgiving mentor. When he found Aelin's swordsmanship to be lacking in her left hand, Arobynn gave her a choice to either break her right hand or have him break it for her. Aelin chose the former.
Arobynn is very cunning, manipulative and possessive. He thinks of Aelin as his possession and does not wish to "share" her with anyone.
Despite his harsh training methods, he is shown to have a kinder side, as Arobynn takes Aelin in to the Assassin's Guild after she seeks refuge there. It is implied that he loved Aelin romantically when he kissed her neck and ordered her to tell him she loved him, under the Valg ring's control.
Arobynn was described as a tall, muscular and handsome man with long auburn hair, silver eyes, and pale skin.
- Combat: As an assassin, Arobynn was highly skilled in combat and weaponry, and possibly in stealth.
Arobynn had a complicated relationship with Aelin, as he treated her harshly and trained her mercilessly to become a feared assassin. Arobynn may have had a romantic interest in Aelin, due to his actions while he believed that she was under his control. Despite whatever he felt for her, Arobynn left nothing to her in his will and spent years keeping the Amulet of Orynth from her, after finding it with her after the murder of her parents.
- Before moving his residence to Rifthold, Arobynn resided in his Keep on the border between Adarlan and Terrasen.
- SJM has stated in her Youtube Channel that Arobynn is the character she miss writing the most.