Given the following context:  The film tells of two very different individuals who share a prison cell in Brazil during the Brazilian military government: Valentin Arregui, who is imprisoned (and has been tortured) due to his activities on behalf of a leftist revolutionary group, and Luis Molina, a transgender woman in prison for having sex with an underage boy. Molina, who self-identifies as "she," passes the time by recounting memories from one of her favorite films, a wartime romantic thriller that's also a Nazi propaganda film. She weaves the characters into a narrative meant to comfort Valentin and distract him from the harsh realities of political imprisonment and separation from his lover, Marta. Valentin encourages Molina to have self-respect and opens her up to political commitment. Despite Valentin's occasionally snapping at Molina over her shallow views of film watching and unrealistic romance, an unlikely friendship develops between the two. As the story develops, it becomes clear that Valentin is being poisoned by his jailers to provide Molina with a chance to befriend him, and that Molina is spying on Valentin on behalf of the secret police. Molina has apparently been promised parole if she succeeds in obtaining information that will allow the secret police to break up the revolutionary group. When Molina declares herself in love with Valentin, a physical consummation of that love occurs on Molina's last night in prison. Molina is granted parole in a surprise move by the secret police. Valentin provides Molina with a telephone number and a message for his comrades. Molina at first refuses to take the number, fearing the consequences of treason, but she relents, bidding Valentin farewell with a kiss.  answer the following question:  What is the last name of the person Luis is in love with?
Answer:
Arregui