What is the target of censorship in Library Wars? What is the target of censorship in the Library Wars (Toshokan Sensō 図書館戦争) franchise? Is it political material, sexual material, or something else?
The premise of Toshokan Sensō involves the Japanese government passing the Media Betterment Act (MBA) as law in 1989 which allows the censorship of any media deemed to be potentially harmful to Japanese society by deploying agents in the Media Betterment Committee (MBC) with the mandate to go after individuals and organizations that are trying to exercise the act of conducting freedom of expression activities in the media. - wikipedia


My interpretation is that the censorship is for everything you mentioned and anything else anyone can think of that would be "harmful to society". Just look at the list of frequently challenged books.

This is the top 10 list for 2012: 

Captain Underpants (series), by Dav Pilkey.
Reasons: Offensive language, unsuited for age group

The Absolutely True Diary of a Part-Time Indian, by Sherman Alexie.
Reasons: Offensive language, racism, sexually explicit, unsuited for age group

Thirteen Reasons Why, by Jay Asher.
Reasons: Drugs/alcohol/smoking, sexually explicit, suicide, unsuited for age group

Fifty Shades of Grey, by E. L. James.
Reasons: Offensive language, sexually explicit

And Tango Makes Three, by Peter Parnell and Justin Richardson.
Reasons: Homosexuality, unsuited for age group

The Kite Runner, by Khaled Hosseini.
Reasons: Homosexuality, offensive language, religious viewpoint, sexually explicit

Looking for Alaska, by John Green.
Reasons: Offensive language, sexually explicit, unsuited for age group

Scary Stories (series), by Alvin Schwartz
Reasons: Unsuited for age group, violence

The Glass Castle, by Jeanette Walls
Reasons: Offensive language, sexually explicit

Beloved, by Toni Morrison
Reasons: Sexually explicit, religious viewpoint, violence