The only way to show the .NET assembly outside the CLR is through COM Interop. You can do nothing to refer to .NET.dll directly in an unmanaged language.
The reason for this is that the .dll file extension is used solely for the visibility and illusion of consistency. The generated .NET .dll files do not contain machine code, they contain IL (intermediate language), which is compiled at run time (Just-In-Time or JIT compilation). The code does not compile when it is placed in a DLL file. As a result, nothing exists for an unmanaged language.
COM interop allows the CLR to load the DLL, execute this JIT compilation, and use the COM system to handle the communication between native code and .NET.dll.