"Yeah. You hear about it on the news and stuff, though. Mums who fuck their sons, dads who fuck their daughters and their sons. Brothers and sisters who fuck each other—"
"Language, please!" Miss Azley protests.
"That's bullshit. Who would want to fuck—sorry, screw—their own parents?"
"It's called incest, man."
"That's when a guy rapes his sister, dickhead."
Tropes relating to incest and its various permutations.
- Alternate Self Shipping: Shipping a character with an alternate duplicate of themself.
- BrotherSister Incest: Incest between siblings. Despite the name, allows both hetero and same-sex incest.
- Big Brother Attraction: A younger sister is strongly attracted to her older brother.
- Father, I Want to Marry My Brother: Little kids telling adults they want to marry a sibling.
- Little Sister Heroine: A little sister who is a love interest.
- My Sister Is Off-Limits!: A brother who bars anyone from dating his sister. May or may not be the result of him having a crush on her himself.
- Not Blood Siblings: It's okay for them to have sex if they're not biologically related.
- Flirty Stepsiblings: A relationship between people who are only related because their parents got together before they did.
- Twincest: Incest between twins. Triplets, quads, etc. fall under BrotherSister Incest.
- Cast Incest: Related characters are played by actors who are lovers in real life.
- Incestuous Casting: A couple is played by actors who are related to each other in real life.
- Creepy Uncle: An uncle with an incestuous interest in his niece or nephew.
- Incest-ant Admirer: When one relative is attracted to the other, but the other is uninterested.
- Incest Subtext: Related characters have interactions that make them look like a couple.
- Incest Yay Shipping: Fans ship characters who are related, especially twins.
- Kissing Cousins: Incest between cousins.
- My Own Grampa: Someone uses time travel and incest to become their own ancestor.
- Parental Incest: Incest between a parent and his/her child, regardless of age. Depending on the age of the child, it can count as pedophilia as well.
- Lecherous Stepparent: A stepparent who is attracted to their stepchild.
- Oedipus Complex: A child is attracted to one of their parents but hates the other.
- Pervert Dad: A father who flirts with and/or acts pervy toward his kid, usually a teenage daughter.
- Wife Husbandry: Raising someone solely so you can marry them once they're old enough.
- Relative Error: Someone mistakes a relative for the person's significant other.
- Royal Inbreeding: Only having sex with blood relatives to keep the bloodline pure (and all the bling and lands within the family), often resulting in the children having birth defects. This was common in medieval England.
- Screw Yourself: Someone has sex with their own clone or other perfectly identical Doppelgänger.
- Surprise Incest: A character enters a relationship with someone, only to later find out they're related. Usually a cousin, a long-lost sibling, or the persons parent from the past (in cases of time travel).
- Villainous Incest: The villain bones one of his relatives to show how vile and messed up he is. This is common with real-life sex offenders as well.
- Inbred and Evil: A villain who was conceived from an incestuous relationship.