diff --git a/rdflib/graph.py b/rdflib/graph.py
index 5d739a95..7b7256d0 100644
--- a/rdflib/graph.py
+++ b/rdflib/graph.py
@@ -2623,7 +2623,7 @@ class Dataset(ConjunctiveGraph):
         file: Optional[Union[BinaryIO, TextIO]] = None,
         data: Optional[Union[str, bytes]] = None,
         **args: Any,
-    ) -> Graph:
+    ) -> Dataset:
         """
         Parse an RDF source adding the resulting triples to the Graph.
 
diff --git a/rdflib/plugins/sparql/update.py b/rdflib/plugins/sparql/update.py
index a6908393..c9d36564 100644
--- a/rdflib/plugins/sparql/update.py
+++ b/rdflib/plugins/sparql/update.py
@@ -182,7 +182,10 @@ def evalModify(ctx: QueryContext, u: CompValue) -> None:
             ctx = ctx.pushGraph(g)
 
     for c in list(res):
-        dg = ctx.graph
+        # TODO: Make this more intentional and without the weird type checking logic
+        #       once ConjunctiveGraph is removed and Dataset no longer inherits from
+        #       Graph.
+        dg = ctx.graph if type(ctx.graph) is Graph else ctx.dataset.default_context
         if u.delete:
             # type error: Unsupported left operand type for - ("None")
             # type error: Unsupported operand types for - ("Graph" and "Generator[Tuple[Identifier, Identifier, Identifier], None, None]")