diff --git a/backend/internal/store/store.go b/backend/internal/store/store.go
index 0658d2b..903e66a 100644
--- a/backend/internal/store/store.go
+++ b/backend/internal/store/store.go
@@ -33,6 +33,9 @@ type Bookmark struct {
 	// Archived series stay polled for new chapters; finished ones do not.
 	// Empty on the way in means "no opinion" — see Upsert.
 	Status string `json:"status"`
+	// Kind is the library bucket: manga or novel. Empty on the way in means
+	// "no opinion" — see Upsert.
+	Kind string `json:"kind"`
 }
 
 // HasNewChapter reports whether the site has published past the read point.
@@ -96,6 +99,14 @@ func (b Bookmark) Initial() string {
 	return "?"
 }
 
+// Library buckets. A bookmark is in exactly one. This cannot be derived from
+// Site: asurascans serves manga and novels from the same /comics/ path, so the
+// userscript that recorded the page is the only party that knows which.
+const (
+	KindManga = "manga"
+	KindNovel = "novel"
+)
+
 // Lifecycle buckets. A bookmark is in exactly one; favorite is orthogonal.
 const (
 	StatusReading  = "reading"
@@ -119,6 +130,7 @@ CREATE TABLE IF NOT EXISTS bookmarks (
   latest_chapter_num REAL,
   latest_checked_at  INTEGER NOT NULL DEFAULT 0,
   status             TEXT NOT NULL DEFAULT 'reading',
+  kind               TEXT NOT NULL DEFAULT 'manga',
   updated_at         INTEGER NOT NULL
 );`
 
@@ -135,11 +147,14 @@ var addedColumns = []struct{ name, ddl string }{
 	// Lifecycle bucket. The DEFAULT backfills every pre-existing row as
 	// 'reading', so there is no separate migration step.
 	{"status", `ALTER TABLE bookmarks ADD COLUMN status TEXT NOT NULL DEFAULT 'reading'`},
+	// Library bucket. The DEFAULT backfills every pre-existing row as 'manga',
+	// which is what every row written before novels existed actually is.
+	{"kind", `ALTER TABLE bookmarks ADD COLUMN kind TEXT NOT NULL DEFAULT 'manga'`},
 }
 
 const bookmarkColumns = `key, site, series_id, title, series_url, cover,
 	last_chapter, last_chapter_num, last_chapter_url,
-	favorite, latest_chapter, latest_chapter_num, updated_at, status`
+	favorite, latest_chapter, latest_chapter_num, updated_at, status, kind`
 
 // Store is the SQLite-backed bookmark store.
 type Store struct {
@@ -296,7 +311,7 @@ func scanBookmark(scan func(...any) error) (Bookmark, error) {
 	if err := scan(
 		&b.Key, &b.Site, &b.SeriesID, &title, &seriesURL, &cover,
 		&lastChapter, &lastChapterNum, &lastChapterURL,
-		&favorite, &latestChapter, &latestChapterNum, &b.UpdatedAt, &status,
+		&favorite, &latestChapter, &latestChapterNum, &b.UpdatedAt, &status, &b.Kind,
 	); err != nil {
 		return Bookmark{}, err
 	}
@@ -384,18 +399,20 @@ func (s *Store) Upsert(b Bookmark) (Bookmark, error) {
 	// is the stored row and excluded.* is the incoming one; a brand-new key
 	// never reaches this clause, so it keeps the fresh timestamp from VALUES.
 	//
-	// The status column resolves on the VALUES side, not in the conflict
-	// clause: excluded.* is the row *after* these expressions are evaluated,
-	// so a default applied there would look identical to a real 'reading' and
-	// would overwrite an archived row on every PUT from a client that knows
-	// nothing about the column. Resolved once here, an empty incoming status
-	// means "keep what is stored", and only a brand-new row falls through to
-	// the literal default. The subquery runs inside this transaction, so it
-	// sees the row this statement is about to conflict with.
+	// The status and kind columns resolve on the VALUES side, not in the
+	// conflict clause: excluded.* is the row *after* these expressions are
+	// evaluated, so a default applied there would look identical to a real
+	// 'reading' / 'manga' and would overwrite an archived or novel row on
+	// every PUT from a client that knows nothing about the column. Resolved
+	// once here, an empty incoming status or kind means "keep what is
+	// stored", and only a brand-new row falls through to the literal
+	// default. The subquery runs inside this transaction, so it sees the
+	// row this statement is about to conflict with.
 	if _, err := tx.Exec(`
 		INSERT INTO bookmarks (`+bookmarkColumns+`)
 		VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?,
-		        COALESCE(NULLIF(?, ''), (SELECT status FROM bookmarks WHERE key = ?), 'reading'))
+		        COALESCE(NULLIF(?, ''), (SELECT status FROM bookmarks WHERE key = ?), 'reading'),
+		        COALESCE(NULLIF(?, ''), (SELECT kind FROM bookmarks WHERE key = ?), 'manga'))
 		ON CONFLICT(key) DO UPDATE SET
 		  site=excluded.site, series_id=excluded.series_id, title=excluded.title,
 		  series_url=excluded.series_url, cover=excluded.cover,
@@ -405,6 +422,7 @@ func (s *Store) Upsert(b Bookmark) (Bookmark, error) {
 		  latest_chapter=excluded.latest_chapter,
 		  latest_chapter_num=excluded.latest_chapter_num,
 		  status=excluded.status,
+		  kind=excluded.kind,
 		  updated_at=CASE
 		    WHEN bookmarks.last_chapter_num IS NOT excluded.last_chapter_num
 		    THEN excluded.updated_at
@@ -413,7 +431,8 @@ func (s *Store) Upsert(b Bookmark) (Bookmark, error) {
 		b.Key, b.Site, b.SeriesID, b.Title, b.SeriesURL, b.Cover,
 		b.LastChapter, b.LastChapterNum, b.LastChapterURL,
 		b.Favorite, b.LatestChapter, latestNum, b.UpdatedAt,
-		b.Status, b.Key); err != nil {
+		b.Status, b.Key,
+		b.Kind, b.Key); err != nil {
 		return Bookmark{}, fmt.Errorf("upsert %q: %w", b.Key, err)
 	}
 
diff --git a/backend/internal/store/store_test.go b/backend/internal/store/store_test.go
index 0653b01..7a29188 100644
--- a/backend/internal/store/store_test.go
+++ b/backend/internal/store/store_test.go
@@ -660,3 +660,104 @@ func TestDisplayChapter(t *testing.T) {
 		t.Errorf("DisplayLatest() = %q, want %q", got, "Ch 11")
 	}
 }
+
+func TestUpsertKindDefaultsToManga(t *testing.T) {
+	store := newTestStore(t)
+	got, err := store.Upsert(Bookmark{
+		Key: "asura:solo", Site: "asura", SeriesID: "solo", UpdatedAt: 1000,
+	})
+	if err != nil {
+		t.Fatalf("Upsert: %v", err)
+	}
+	if got.Kind != KindManga {
+		t.Fatalf("Kind = %q, want %q", got.Kind, KindManga)
+	}
+}
+
+func TestUpsertKindRoundTrips(t *testing.T) {
+	store := newTestStore(t)
+	got, err := store.Upsert(Bookmark{
+		Key: "lightnovelworld:a-will-eternal", Site: "lightnovelworld",
+		SeriesID: "a-will-eternal", Kind: KindNovel, UpdatedAt: 1000,
+	})
+	if err != nil {
+		t.Fatalf("Upsert: %v", err)
+	}
+	if got.Kind != KindNovel {
+		t.Fatalf("Kind = %q, want %q", got.Kind, KindNovel)
+	}
+}
+
+// The real hazard: a client that predates the column sends no kind at all. That
+// must keep the stored library, not silently demote a novel to manga.
+func TestUpsertEmptyKindKeepsStoredValue(t *testing.T) {
+	store := newTestStore(t)
+	if _, err := store.Upsert(Bookmark{
+		Key: "lightnovelworld:a-will-eternal", Site: "lightnovelworld",
+		SeriesID: "a-will-eternal", Kind: KindNovel, LastChapterNum: 10, UpdatedAt: 1000,
+	}); err != nil {
+		t.Fatalf("seed: %v", err)
+	}
+
+	got, err := store.Upsert(Bookmark{
+		Key: "lightnovelworld:a-will-eternal", Site: "lightnovelworld",
+		SeriesID: "a-will-eternal", Kind: "", LastChapterNum: 11, UpdatedAt: 2000,
+	})
+	if err != nil {
+		t.Fatalf("Upsert: %v", err)
+	}
+	if got.Kind != KindNovel {
+		t.Fatalf("Kind = %q, want %q — an empty kind must not reset the library", got.Kind, KindNovel)
+	}
+	if got.LastChapterNum != 11 {
+		t.Fatalf("LastChapterNum = %v, want 11 — progress in the same request must still land", got.LastChapterNum)
+	}
+}
+
+// A database created before this column exists must gain it, backfilled as
+// manga, without losing anything.
+func TestLegacyDatabaseGainsKindAsManga(t *testing.T) {
+	dbPath := filepath.Join(t.TempDir(), "legacy.db")
+
+	legacy, err := sql.Open("sqlite", dbPath)
+	if err != nil {
+		t.Fatalf("open legacy db: %v", err)
+	}
+	if _, err := legacy.Exec(`
+		CREATE TABLE bookmarks (
+		  key              TEXT PRIMARY KEY,
+		  site             TEXT NOT NULL,
+		  series_id        TEXT NOT NULL,
+		  title            TEXT,
+		  series_url       TEXT,
+		  cover            TEXT,
+		  last_chapter     TEXT,
+		  last_chapter_num REAL,
+		  last_chapter_url TEXT,
+		  updated_at       INTEGER NOT NULL
+		)`); err != nil {
+		t.Fatalf("create legacy schema: %v", err)
+	}
+	if _, err := legacy.Exec(`
+		INSERT INTO bookmarks (key, site, series_id, title, updated_at)
+		VALUES ('asura:legacy', 'asura', 'legacy', 'Legacy Series', 123)`); err != nil {
+		t.Fatalf("seed legacy row: %v", err)
+	}
+	if err := legacy.Close(); err != nil {
+		t.Fatalf("close legacy db: %v", err)
+	}
+
+	store, err := Open(dbPath)
+	if err != nil {
+		t.Fatalf("Open on legacy db: %v", err)
+	}
+	t.Cleanup(func() { store.Close() })
+
+	list, err := store.List()
+	if err != nil {
+		t.Fatalf("List: %v", err)
+	}
+	if len(list) != 1 || list[0].Kind != KindManga {
+		t.Fatalf("legacy row should backfill as manga, got %+v", list)
+	}
+}