diff --git a/include/pocketpy/vm.h b/include/pocketpy/vm.h
index 72e6ba9d..2f10c573 100644
--- a/include/pocketpy/vm.h
+++ b/include/pocketpy/vm.h
@@ -460,7 +460,7 @@ public:
     // new style binding api
     PyObject* bind(PyObject*, const char*, const char*, NativeFuncC, UserData userdata={}, BindType bt=BindType::DEFAULT);
     PyObject* bind(PyObject*, const char*, NativeFuncC, UserData userdata={}, BindType bt=BindType::DEFAULT);
-    PyObject* bind_property(PyObject*, Str, NativeFuncC fget, NativeFuncC fset=nullptr);
+    PyObject* bind_property(PyObject*, const char*, NativeFuncC fget, NativeFuncC fset=nullptr);
 
     template<typename T>
     Type _find_type_in_cxx_typeid_map(){
diff --git a/src/vm.cpp b/src/vm.cpp
index 94dde907..ef6724ae 100644
--- a/src/vm.cpp
+++ b/src/vm.cpp
@@ -1204,14 +1204,15 @@ PyObject* VM::bind(PyObject* obj, const char* sig, const char* docstring, Native
     return f_obj;
 }
 
-PyObject* VM::bind_property(PyObject* obj, Str name, NativeFuncC fget, NativeFuncC fset){
+PyObject* VM::bind_property(PyObject* obj, const char* name, NativeFuncC fget, NativeFuncC fset){
     PyObject* _0 = heap.gcnew<NativeFunc>(tp_native_func, fget, 1, false);
     PyObject* _1 = vm->None;
     if(fset != nullptr) _1 = heap.gcnew<NativeFunc>(tp_native_func, fset, 2, false);
-    int pos = name.index(":");
-    if(pos > 0) name = name.substr(0, pos).strip();
+    std::string_view name_sv(name);
+    int pos = name_sv.find(':');
+    if(pos > 0) name_sv = name_sv.substr(0, pos);
     PyObject* prop = VAR(Property(_0, _1));
-    obj->attr().set(name, prop);
+    obj->attr().set(StrName(name_sv), prop);
     return prop;
 }