Vulture was Berg's nickname.
Ever since he became a "freelance mercenary," he had been known by this moniker.
He was acutely aware of the impact his real name's disclosure could have if he still wished to save enough money to return to his homeland and live a wealthy, safe life; it was best to temporarily forget his real name.
This was the very principle his guide and teacher had "taught" him.
He had always kept it in mind.
Because his teacher was killed by him in the second year of his retirement.
Why?
Of course, for money!
He had long coveted his teacher's ever-bountiful pension.
Unfortunately, when the money was split among several people, the seemingly generous pension didn't seem so substantial anymore.
Vulture wanted to kill off a few partners, but these partners were exceptionally shrewd; after splitting the money, none of them were willing to have a drink with him, all left in a hurry.
It was a pity for that bottle of poison-laced wine.