He was described as being a six-armed, two-headed Night Lich.
Benjeli Ansis was one of the oldest member of the Corpus of the Abyss's inner circle. He was said to be also one of the founders of the undead organization.
The Vampire Princess of the Lost Country Arc
- Main article: The Vampire Princess of the Lost Country Arc
That one day in particular, it was said he had been paying a visit for the stronghold of Granz Locke to learn how he reach the 8th tier. However, growing suspicious the longer he waited for Granz's servants to arrive and guide him there, Benjeli summoned his own minions and cautiously entered the lich's stronghold, where he immediately realized what had happened. He noticed that everything belonging to Granz including his research and wealth had been taken away. 
Abilities and Powers
Benjeli Ansis is skillfully familiar with the use of 6th-tier arcane spells and 6th-tier spells from other traditions. Due to the power he possesses, Benjeli is regarded as a fearsome being that humanity could not overcome. Benjeli is also skilled in riding an undead dragon.
Like the necromancers in Corpus of the Abyss, he is capable of summoning undead minions under his control.
It seems Bejeli had a cordial relationship with Granz wherein which he had to pay some various fees in reaching his fellow member's stronghold.