Basic Trope: Teenage stepsiblings are romantically involved with each other.
- Straight: Alice is dating her stepbrother Bob. Alice's mother Carol has recently married Bob's father David.
- Exaggerated: Within hours of Dave and Carol's wedding, Dave's three sons pair off with Carol's three daughters and they all have sex.
- Downplayed: Carol and David have a December–December Romance and marry. Their grown-up children Alice and Bob then develop an interest in each other.
- Justified:
- They weren't raised together, so they have no real reason to view each other as siblings. They're compatible as a couple, and they're also horny teens now in very close proximity.
- Alice and Bob are classmates, and had a crush on each other before their parents started dating.note
- Inverted: Teenage classmates Alice and Bob are dating. Because their children were in a relationship first, when Alice's mom Carol and Bob's dad David start dating, this is seen as somewhat taboo and they try to keep the relationship under wraps.
- Subverted: Alice and Bob's parents are dating. When they're introduced to each other, they're attracted to each other. For a while it looks like their parents might marry, but in the end they break up instead.
- Double Subverted: ???
- Parodied: Alice and her mother Carol argue about whether Alice saw Bob first, or if Carol saw David first. It's agreed that whichever one saw her love interest first has the right to pursue the relationship.
- Averted: Alice and Bob have no attraction to each other.
- Enforced: The actors have chemistry, and their interactions come off as flirty regardless. So the writers work this into the script as a form of Lampshade Hanging.
- Lampshaded:Ethan: He's your brother, Alice!
Alice: We're not related and we didn't grow up together. How is he my brother? - Invoked: Bob has a crush on Alice, so he plays The Match Maker for their parents so he'll be closer to her.
- Exploited: ???
- Defied: Carol and David have both had trouble dating in the past. Because Alice and Bob care about their parents, and see how happy being together makes them, they decide it would be selfish of them to jeopardize that by dating themselves.
- Implied: Incest Subtext
- Discussed: ???
- Conversed: ???
- Deconstructed: After breaking up with Bob, living in the same house with him is too painful, so Alice has to seek out her Disappeared Dad and live with him instead.
- Reconstructed:
- Alice is almost old enough to move out anyway. She only has to live with her dad for a few months before starting university and moving a dorm there.
- Alice and Bob's repressed attraction manifested as Belligerent Sexual Tension, and that caused far more drama in the household than their relationship ever did.
Back to Flirty Stepsiblings—it's a link, but only because their parents got married last year.
