I think Raphael is exactly what he appears to be. He wants your tadpoles, and he wants your souls, and he's willing to do pretty much whatever to get them. The tadpoles grant you power, and my theory is that they wouldn't actually work on Raphael, as he is a Devil, but it would still bond to him, as he is part human. He wants their power, I think.
He must know how to avoid any collateral effect... He is very powerful and smart and he knows a lot about ceremorphosis, maybe does he know at this point how to use the tadpole powers without risks?🤔
