20th Century (incl. WWII): 24 trope pairings readers ask for, each with the counted reader asks in this lane naming both tropes together and the counted trope-tagged titles carrying both. 12 are open gaps. Free, no sign-up.
| Pairing readers ask for | Reader asks in this lane | Titles carrying both | Verdict |
|---|---|---|---|
| Dual Timeline + Found Family separately: 9 and 345 tagged titles | 346 | 3 | Open gap 115.3 asks per published title |
| Dual Timeline + Family Saga separately: 9 and 7 tagged titles | 57 | 0 | Never written together both tropes are published; no tagged title carries both |
| Dual Timeline + Family Secrets separately: 9 and 19 tagged titles | 166 | 3 | Open gap 55.3 asks per published title |
| Dual POV + Dual Timeline separately: 19 and 9 tagged titles | 35 | 0 | Never written together both tropes are published; no tagged title carries both |
| Found Family + Sisterhood separately: 345 and 306 tagged titles | 30 | 0 | Never written together both tropes are published; no tagged title carries both |
| Dual Timeline + Mystery / Suspense Element separately: 9 and 56 tagged titles | 74 | 3 | Open gap 24.7 asks per published title |
| Espionage + Found Family separately: 143 and 345 tagged titles | 31 | 1 | Open gap 31.0 asks per published title |
| Found Family + Survival separately: 345 and 669 tagged titles | 74 | 4 | Open gap 18.5 asks per published title |
| Family Secrets + Mystery / Suspense Element separately: 19 and 56 tagged titles | 47 | 3 | Open gap 15.7 asks per published title |
| Dual Timeline + Slow Burn separately: 9 and 296 tagged titles | 33 | 2 | Open gap 16.5 asks per published title |
| Character Growth + Found Family separately: 9 and 345 tagged titles | 30 | 2 | Open gap 15.0 asks per published title |
| Dual Timeline + Second Chance separately: 9 and 309 tagged titles | 58 | 6 | Thin on the shelf 9.7 asks per published title |
| Dual POV + Found Family separately: 19 and 345 tagged titles | 41 | 4 | Open gap 10.3 asks per published title |
| Emotional Journey + Found Family separately: 9 and 345 tagged titles | 39 | 4 | Thin on the shelf 9.8 asks per published title |
| Family Secrets + Found Family separately: 19 and 345 tagged titles | 52 | 7 | Thin on the shelf 7.4 asks per published title |
| Mystery / Suspense Element + Plot Twists separately: 56 and 38 tagged titles | 45 | 7 | Thin on the shelf 6.4 asks per published title |
| Found Family + Self Discovery separately: 345 and 12 tagged titles | 56 | 9 | Thin on the shelf 6.2 asks per published title |
| Found Family + Sacrifice separately: 345 and 1,005 tagged titles | 33 | 5 | Thin on the shelf 6.6 asks per published title |
| Found Family + Redemption Arc separately: 345 and 47 tagged titles | 78 | 15 | Thin on the shelf 5.2 asks per published title |
| Found Family + Trauma Recovery separately: 345 and 17 tagged titles | 32 | 10 | Thin on the shelf 3.2 asks per published title |
| Found Family + Mystery / Suspense Element separately: 345 and 56 tagged titles | 47 | 16 | Well served 2.9 asks per published title |
| Fish Out of Water + Found Family separately: 66 and 345 tagged titles | 30 | 28 | Well served 1.1 asks per published title |
| Found Family + Second Chance separately: 345 and 309 tagged titles | 92 | 105 | Well served 0.9 asks per published title |
| Found Family + Slow Burn separately: 345 and 296 tagged titles | 102 | 124 | Well served 0.8 asks per published title |
Reader asks is a counted number: parsed reader requests — from Goodreads and Amazon reviews and Q&A, Reddit and BookTok — in which a reader writing about this lane named both tropes in the same request. 2,585,660 reader signals sit behind it. Titles carrying both is counted the same way over published titles tagged trope by trope: 114,151 distinct titles, 952,697 trope tags. Neither number is modelled, sampled or estimated.
Two things to be straight about. The supply count is registry-wide, not lane-scoped — our demand data and our title tagging use different subgenre vocabularies, and rather than fake a join we count titles carrying both tropes anywhere in the tagged registry. And a pairing is only listed when both of its tropes carry at least five tagged titles on their own (the two figures are printed under each pairing), so a zero in the “carrying both” column means the pairing really is unwritten in what we have tagged, not that we simply never tagged the trope.
The verdict column is a rule, printed here so you can apply it yourself: ten or more asks per published title is an open gap; three to ten is thin on the shelf; below three is well served; and a pairing readers ask for that no tagged title in the lane carries at all is called out as such. Pairings with fewer than three asks are not listed — too few to mean anything.
What it is not. It is not a sales forecast and it is not advice to write anything. A gap can be a gap because readers ask and nobody delivers, or because the pairing does not work. That judgement is yours; the counting is ours. Counted 2026-10-06 and restated whenever the corpus is recounted — the raw JSON behind any lane is one query string away.
Free to embed on any blog, newsletter template or author site. The widget renders the pairing board for this lane and must keep its visible “Data: Tropesmith” credit link — that link back to tropesmith.com is the licence, and it is written into the payload server-side so it cannot be shipped without it.
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