Is there any book anywhere that couldn't be in need of a trigger warning? Think about Twilight or Lord of the Rings or The Great Gatsby. What would be helpful is for professors to do what many I know already do: ask students at the beginning of a class to inform them privately if they have any issues that might interfere with classroom learning and proceed from there.
Mayra Arce even resembles Esperanza, the protagonist in The House on Mango Street, one of the 80-plus books that were part of the Tucson Unified School District's K-12 Mexican-American studies curriculum before the program was dismantled under Arizona House Bill 2281. But Maya isn't the main character of a book. She's the main plaintiff in the lawsuit against Arizona.
I am well aware that any depiction of human relationships in a novel cannot ignore the fact that sex, however described or disguised, is a primal motivating condition of our existence. Indeed, even if the act itself is not referred to in action or description, it is always there, however coded, and can't be ignored by reader or writer.
How disappointing that a majority of the school board chose to disregard student protests and pass a curriculum review proposal designed to identify "objectionable materials" in high school curricula, starting with U.S. history, presumably to remove those materials if they do not meet the ideological criteria of the school board members.