This series deals with the following subjects :

Physical violence

Psychological violence

Mention of rape

Attempted rape

Mutilation

Depression

Blackmail

Suicidal thoughts

Suicide attempt

Incest

Assassination

Human traffic

Child trafficking

Child abuse

Child murder

Mention of cannibalism

Slavery

War

Discrimination

LGBT+ characters and relationship

Poly relationship

Some of them don't appear in this particular volume but they will appear later on in the series.

Also, english is not my first language so I apologize in advance for any mistakes.