Question: What is the final book in the series that depicts a society that has eliminated emotion and color to attempt to achieve equality?

Context articles: Scarlet Alliance
Moser Gender Planning Framework
The Cutie Map
SOS Homophobie
Stand to Reason (UK charity)
Die Urbane. Eine HipHop Partei
Feminism and equality
HeForShe
Son (novel)
The Giver

Scarlet Alliance is Australia's national peak sex worker organisation.
 It was formed in 1989.
 As an organisation maintained entirely by current and former sex workers, Scarlet Alliance aims to achieve equality, social, legal, political, cultural and economic justice for workers in the sex industry.
The Moser Gender Planning Framework is a tool for gender analysis in development planning.
 It was developed by Caroline Moser.
 The goal is to free women from subordination and allow them to achieve equality, equity, and empowerment.
"The Cutie Map", also known as "Cutie Markless" by Shout!
 Factory and iTunes, is the collective name for the first and second episodes of the of the Canadian–American animated television series "" as well as the ninety-second and ninety-third episodes of the series overall.
 The two episodes focus on the group of and her friends as they visit a village controlled by , a unicorn who strives to achieve equality amongst all ponies by removing their cutie marks (individual talents).
 Both episodes were written by Scott Sonneborn and M.A. Larson from a story by Meghan McCarthy.
 It is directed by Jayson Thiessen and co-directed by Jim Miller with Stephen Davis, Kirsten Newlands, and Sarah Wall as executive producers alongside Devon Cody as producer.
 It was first broadcast on Discovery Family on April 4, 2015, with both parts airing as an hour-long event.
SOS Homophobie is a LGBT support organization based in France that deals with homophobia.
 The organization currently consists of a 900 volunteer members as well as 17 regional offices, all of which are based in France.
 The group is frequently mentioned on various media such as social media sites, television, and print.
 SOS Homophobie provides national support programs including an anonymous hotline, testimonials on websites and support offered through postal mail.
 The main objectives of the organization are to support those who have fallen victim to homophobia and to run homophobia prevention events.
 Moreover, the organization aims to ultimately achieve equality between homosexual and heterosexual couples, and equal treatment for people despite sexual orientation.
Stand to Reason is a UK-based mental health charity which aims to raise the profile of people who are mentally ill, fight prejudice, establish rights and achieve equality.
Die Urbane.
 Eine HipHop Partei (The Urbans.
 A HipHop Party) is a German political party founded in Berlin in February 2017 which locate themselves within the Hip hop culture.
 The main goals of the party include first and foremost social justice; their self-proclaimed goal is to achieve equality among all citizens.
 During the German federal election in September 24, 2017, they are among the parties listed in the federal state of Berlin.
Feminism typically refers to gender equality especially with respect to rights for female humans, even though many feminist movements and ideologies differ on exactly which claims and strategies are vital and justifiable to achieve equality.
HeForShe (often referred to as He for She) is a solidarity campaign for the advancement of women initiated by UN Women.
 Its goal is to achieve equality by encouraging men and boys as agents of change and take action against negative inequalities faced by women and girls.
 Grounded in the idea that gender equality is an issue that affects all people—socially, economically and politically—it seeks to actively involve men and boys in a movement that was originally conceived as "a struggle for women by women".
Son is the final entry in "The Giver Quartet" by Lois Lowry.
 It was preceded by "Messenger", the third book of the series.
 The book follows Claire, the mother of Gabriel, the baby seen in "The Giver".
The Giver is a 1993 American young adult dystopian novel by Lois Lowry.
 It is set in a society which at first appears to be utopian but is revealed to be dystopian as the story progresses.
 The novel follows a 12-year-old boy named Jonas.
 The society has eliminated pain and strife by converting to "Sameness", a plan that has also eradicated emotional depth from their lives.
 Jonas is selected to inherit the position of Receiver of Memory, the person who stores all the past memories of the time before Sameness, as there may be times where one must draw upon the wisdom gained from history to aid the community's decision making.
 Jonas struggles with concepts of all the new emotions and things introduced to him: whether they are inherently good, evil, or in between, and whether it is even possible to have one without the other.
 The Community lacks any color, memory, climate, or terrain, all in an effort to preserve structure, order, and a true sense of equality beyond personal individuality.