Angelina fell in love with Vincent Phantomhive when she was fifteen, but becomes distraught when she found out that her sister was marrying him. Because she was very close to her sister and cared deeply for her, she tried to be happy that the two people she loved most were getting married. However, after their marriage, she came to hate the color red again. After Ciel was born, she worked to earn her doctor's license, against the wishes of her parents. She also attended lavish parties, which she stated that she hated, in red dresses and was then renowned as Madam Red. She frequently played with Ciel and Elizabeth Midford, stating that these were the people she loved the most.
Fitting her title as "Madam Red", Angelina is almost always clad in red clothing and makeup, normally consisting of a red skirt and matching waistcoat, under which is worn a ruffled white blouse. She also often wears a red hat and carries a red parasol. She tends to wear black gloves. Her crimson hair is kept in a bobcut. Her eyes are the same color.
She initially hated her red hair that was inherited from her father, and she usually covered it up and kept her bangs long to hide her face, until Vincent Phantomhive stated he liked her hair, which he said reminded him of "red spider lilies in full bloom." After this, Angelina cut her bangs and always dressed in red.
In the past, Angelina was quite withdrawn and shy because of her red hair and admired and loved her sister, Rachel Phantomhive. However, in the present she has a crude and frivolous nature. For example, she suggests Sebastian Michaelis should work for her on account of him being handsome whilst stroking his backside. She also attempts to make Undertaker laugh by telling a dirty joke.
Her belief is that ladies are more attractive to others if they act innocent, naive, fragile, and cheerful, particularly around their lords. Nevertheless, they should also smile often and appear oblivious to troubles.
Her fluctuating like and dislike for the color red corresponds to the events that occur in her life. She falls in love with Vincent Phantomhive and she consequently liked red. She was generally lighthearted about her sister's and Vincent's marriage, saying if the two people she loved most are happy, she is happy as well, although she began to dislike red again. Afterwards, she loses her husband and baby and when the rest of her family died in the fire, she described the color as crimson red, the color she hated the most.
She appears to care deeply about Ciel Phantomhive, treating him like her own son, and tries to convince him to not pursue in the darker side of society but to aim for a happier life but he insisted otherwise. Soon after, she asks Sebastian to stay by Ciel's side to protect him. The losses of family members left her lugubrious and she harbors a general disregard for human life, as she works with Grell Sutcliff to perform the Jack the Ripper murders. Nonetheless, she cannot bring herself to kill Ciel when encouraged to by Grell.
Later in her life Angelina married Baron Barnett, who treated her lovingly and gently, stating that he did not mind that she harbored feelings for another. She called him an honest and pure man who treated her well and made her happy. She became pregnant, but after a carriage accident in which her husband was killed, her womb and unborn child had to be removed to save her own life. Rachel frequently visited her in the hospital, understanding the pain she was in. However, Angelina became even more bitter about her sister's marriage, as Rachel had Ciel while Angelina could now never have children of her own. Her loss also caused her great strife as a doctor, as she regularly performed abortions on prostitutes, who considered pregnancy nothing but a nuisance.
After Angelina recovered, Rachel invited her to Ciel's tenth birthday party; Angelina stated she did not really want to attend, but went anyway. Upon arriving, she witnessed the Phantomhive manor burning and learned that Rachel and her husband were killed and Ciel's body was never found. This was caused by the color she hated - the burning red of the fire. She was devastated by the news, but all the same, envious of her sister because she died with the person she loved, while Angelina had to carry on living.