diff --git a/application/world/services/bible_service.py b/application/world/services/bible_service.py
index 8970beebb..72258bead 100644
--- a/application/world/services/bible_service.py
+++ b/application/world/services/bible_service.py
@@ -13,7 +13,7 @@
 from domain.bible.repositories.bible_repository import BibleRepository
 from domain.novel.repositories.novel_repository import NovelRepository
 from domain.novel.repositories.chapter_repository import ChapterRepository
-from domain.shared.exceptions import EntityNotFoundError
+from domain.shared.exceptions import EntityNotFoundError, InvalidOperationError
 from application.world.dtos.bible_dto import BibleDTO, CharacterDTO
 
 if TYPE_CHECKING:
@@ -105,7 +105,7 @@ def add_character(
         description: str,
         relationships: list = None
     ) -> BibleDTO:
-        """添加人物
+        """添加人物（增量写入，不触碰已有角色和关系）
 
         Args:
             novel_id: 小说 ID
@@ -124,15 +124,41 @@ def add_character(
         if bible is None:
             raise EntityNotFoundError("Bible", f"for novel {novel_id}")
 
-        character = Character(
-            id=CharacterId(character_id),
-            name=name,
-            description=description,
-            relationships=relationships or [],
-        )
-        bible.add_character(character)
-        self.bible_repository.save(bible)
+        # 检查角色是否已存在
+        if bible.get_character(CharacterId(character_id)) is not None:
+            raise InvalidOperationError(
+                f"Character with id '{character_id}' already exists"
+            )
 
+        # 增量写入：只 INSERT 新角色及其关系，不 DELETE 其他数据
+        repo = self.bible_repository
+        if hasattr(repo, "add_character_incremental"):
+            rel_dicts = []
+            for rel in (relationships or []):
+                if isinstance(rel, dict):
+                    rel_dicts.append(rel)
+                elif hasattr(rel, "model_dump"):
+                    rel_dicts.append(rel.model_dump())
+                elif hasattr(rel, "dict"):
+                    rel_dicts.append(rel.dict())
+                else:
+                    rel_dicts.append({"target": str(rel), "relation": "", "description": ""})
+            repo.add_character_incremental(
+                novel_id, character_id, name, description, rel_dicts,
+            )
+        else:
+            # fallback：非 SQLite 仓储走原路径
+            character = Character(
+                id=CharacterId(character_id),
+                name=name,
+                description=description,
+                relationships=relationships or [],
+            )
+            bible.add_character(character)
+            repo.save(bible)
+
+        # 重新加载最新状态返回
+        bible = self.bible_repository.get_by_novel_id(NovelId(novel_id))
         return BibleDTO.from_domain(bible)
 
     def update_character_voice_anchors(
diff --git a/infrastructure/persistence/database/sqlite_bible_repository.py b/infrastructure/persistence/database/sqlite_bible_repository.py
index 52fffb590..b2c4cdb79 100644
--- a/infrastructure/persistence/database/sqlite_bible_repository.py
+++ b/infrastructure/persistence/database/sqlite_bible_repository.py
@@ -315,6 +315,51 @@ def exists(self, bible_id: str) -> bool:
         r = self.db.fetch_one("SELECT 1 AS o FROM bibles WHERE id = ?", (bible_id,))
         return r is not None
 
+    def add_character_incremental(
+        self,
+        novel_id: str,
+        character_id: str,
+        name: str,
+        description: str,
+        relationships: List[Dict[str, str]],
+        *,
+        mental_state: str = "NORMAL",
+        verbal_tic: str = "",
+        idle_behavior: str = "",
+    ) -> None:
+        """增量添加单个角色及其关系（不触碰其他角色）。"""
+        now = self._now()
+        conn = self._conn()
+        try:
+            conn.execute(
+                """
+                INSERT OR REPLACE INTO bible_characters (
+                    id, novel_id, name, description,
+                    mental_state, mental_state_reason, verbal_tic, idle_behavior,
+                    created_at, updated_at
+                ) VALUES (?, ?, ?, ?, ?, '', ?, ?, ?, ?)
+                """,
+                (character_id, novel_id, name, description,
+                 mental_state, verbal_tic, idle_behavior, now, now),
+            )
+            for i, rel in enumerate(relationships):
+                rid = f"{character_id}-rel-{i}-{uuid.uuid4().hex[:6]}"
+                target_name = rel.get("target", "") or ""
+                relation = rel.get("relation", "") or ""
+                desc = rel.get("description", "") or ""
+                conn.execute(
+                    """
+                    INSERT INTO bible_character_relationships
+                    (id, character_id, target_name, relation, description)
+                    VALUES (?, ?, ?, ?, ?)
+                    """,
+                    (rid, character_id, target_name, relation, desc),
+                )
+            conn.commit()
+        except Exception:
+            conn.rollback()
+            raise
+
     def update_character_anchors(
         self,
         novel_id: str,
diff --git a/tests/unit/application/services/test_bible_service.py b/tests/unit/application/services/test_bible_service.py
index 9813335aa..dac071cda 100644
--- a/tests/unit/application/services/test_bible_service.py
+++ b/tests/unit/application/services/test_bible_service.py
@@ -40,9 +40,13 @@ def test_create_bible(self, service, mock_repository):
 
     def test_add_character(self, service, mock_repository):
         """测试添加人物"""
-        # 准备 mock 数据
-        bible = Bible(id="bible-1", novel_id=NovelId("novel-1"))
-        mock_repository.get_by_novel_id.return_value = bible
+        # 准备 mock 数据：第一次返回空 Bible，第二次返回含角色的 Bible（模拟增量写入后）
+        bible_empty = Bible(id="bible-1", novel_id=NovelId("novel-1"))
+        bible_with_char = Bible(id="bible-1", novel_id=NovelId("novel-1"))
+        bible_with_char.add_character(
+            Character(id=CharacterId("char-1"), name="主角", description="主角描述")
+        )
+        mock_repository.get_by_novel_id.side_effect = [bible_empty, bible_with_char]
 
         bible_dto = service.add_character(
             novel_id="novel-1",
@@ -56,8 +60,8 @@ def test_add_character(self, service, mock_repository):
         assert bible_dto.characters[0].id == "char-1"
         assert bible_dto.characters[0].name == "主角"
 
-        # 验证调用了 save
-        mock_repository.save.assert_called_once()
+        # 验证调用了增量写入
+        mock_repository.add_character_incremental.assert_called_once()
 
     def test_add_character_bible_not_found(self, service, mock_repository):
         """测试向不存在的 Bible 添加人物"""