* FridgeHorror: So, apparently everyone is matched according to genetic compatibility, rather than preference. This obviously means a person of the opposite sex. They have no choice in this, and it's permanent. What happens to homosexuals?
** They would probably choose to be Singles.
** Another example: The [[spoiler:red pill]]. The fact that it can cause the people who aren't immune to lose their [[spoiler:memories]] over the past twelve hours, which means that the Society [[spoiler:can basically make up any story and brainwash their citizens if they need to hide anything. Case in point: what actually happened to Matthew Markham]].
** The fact that the Society actually [[spoiler:''poisons'']] the elderly to ensure that [[spoiler:they actually die when the Society says so]].
* {{Ship To Ship Combat}}: Team Xander vs. Team Ky, with Cassia/Ky being the {{Fan Preferred Couple}}... in a book about how matching others is wrong, meaning...
** DoNotDoThisCoolThing
* {{Tear Jerker}}: Grandfather's death.
** Also [[spoiler: Vick's sudden violent death]] in ''Crossed'', especially when [[spoiler: Ky]] carves that little fish for his gravesite.
* {{Iron Woobie}}: Ky.
* XMeetsY: ''TheHungerGames'' meets ''TheGiver''.