𝐵𝓇𝒾𝑒𝒻 𝑅𝑒𝓉𝓊𝓇𝓃 𝓉𝑜 𝑀𝑜𝓇𝓉𝒶𝓁𝒾𝓉𝓎.

When Dorian was confronted by Evelyn for the first time, she had made him suffer greatly as well as killing his maker Lilith before his eyes. Not only having ripped a great part of his life away before his eyes she also used her dark magic to make him mortal and kept him alive for her own sick personal torture as death was too good for him for having worked with Lilith in killing her six daughters those centuries ago. 

Having used Sebastian as a tool to collect certain 'ingredients' from Dorian's body for her magic to control his own free will making him walk in the sunlight while he was still a vampire, she let him just about burn to death before calling him back into the darkness. She toyed with him emotionally and physically and after making him mortal she would take more from him, this time his right leg. She was in the process of going to tear him limb from limb and feed him to a pack of werewolves though only got so far as to his right leg before someone came to his rescue, the demon who got him in that position himself; Sebastian.

Sebastian couldn't take anymore of Evelyn's sick torment and killed her. Her spell of making him mortal was broken, allowing Dorian to become immortal again though the damage was done physically during his mortality. 

Dorian has a prosthetic right leg, with the far advancement of technology and several months of physical therapy and still to this day dealing with phantom limb, Dorian will never fully be complete. His vampiric abilities only being able to heal what it can while he is a vampire. The scarce reality of having gone back to being a mortal haunts Dorian and his fear of witches has only ever increased and anyone who can ever turn him mortal he stays as far away as possible from them.