Meet Joe Black

Billionaire media mogul William "Bill" Parrish is considering a merger between his company and another media giant, while also about to celebrate his 65th birthday with an elaborate party being planned by his eldest daughter Allison. He begins to hear mysterious voices, which he tries with increasing difficulty to ignore. His youngest daughter Susan, an internal medicine resident, is involved with one of Bill's board members, Drew. She is considering marriage, but her father can tell she's not passionately in love. When she asks for the short version of his impassioned speech, he simply says, "Stay open. Who knows? Lightning could strike!"
Susan meets a vibrant young man at a coffee shop. She is instantly enamored but fails to even get his name. Minutes after their encounter (but unbeknownst to her), the man is struck by multiple cars in what appears to be a fatal motor vehicle accident. Death arrives at Bill's home in the body of the young man, explaining that Bill's impassioned speech has piqued his interest. Given Bill's "competence, experience, and wisdom," Death says that for as long as Bill will be his guide on Earth, he will not have to die. Making up a name on the spot, Death is introduced to the family as "Joe Black."
Bill's best efforts to navigate the next few daysâknowing them now to be his lastâfail to keep events from going rapidly out of his control. Drew is secretly conspiring with a man bidding for Parrish Communications. He capitalizes on Bill's strange behavior and unexplained reliance on Joe Black to convince the board to vote him out as Chairman, using information given to him inadvertently by Bill's son-in-law, Quince, to push through approval for the merger which Bill had decided to oppose. Quince is devastated.
Although confused by the sudden reappearance of Joe, believing him to be the young man from the coffee shop, Susan eventually falls deeply in love with him. Joe is now under the influence of human desires and becomes attracted to her as well. Bill angrily confronts him about his relationship with his daughter, but Death (personified in Joe) declares his intention to take Susan with him for his own.
As his last birthday arrives, Bill appeals to Joe to recognize the meaning of true love and all it encompassesâespecially honesty and sacrifice. Joe comes to understand that he must set aside his own desire and allow Susan to live her life. He also helps Bill regain control of his company, exposing Drew's underhanded business dealings to the board by "revealing" himself to be an agent of the Internal Revenue Service and threatening to put Drew in jail.
Bill devotes his remaining hours of life to his daughters at the party. Joe says a last goodbye to Susan, who seems to finally sense his true purpose and identity. As fireworks appear in the distance, Susan watches as Joe and her father walk out of view. Bill expresses to Joe, trepidation; but Joe assures him that in this "future" (while it may be unknown to him), he has nothing to fear. After a few moments (with both her father and "Joe" now gone), Joe reappears, alone. Death appears to have departed (with Bill), leaving Susan's young man from the coffee shop, unaware of how he got to Susan's father's party. While Susan (in this new reality's timeline), is now both aware of (and accepting), that her father has gone; and she welcomingly reignites the mutual bonding with the man she had met in the coffee shop (and who had "disappeared"; a few days earlier). During their conversation, there are hints to the audience whether or not the man is truly the young man from the coffee shop, or is it really still Death. Susan asks, "What do we do now?" (A question that took place between her and Death/Joe earlier on). The man replies with, "It will come to us." They both hold hands and look out, watching the fireworks at its end.

Question: Who did Joe say goodbye to, before leaving with Bill?
Answer: Susan.