Haygoth

Haygoth was a Zygon warlord who fell in love with a human named Patricia Ryder, and hid himself from other Zygons as a human named Trevor. When Patricia was killed by Trevor's former warriors, unknown to Lucie Miller, Pat's niece, her husband decided to keep her shape, to honor her. (AUDIO: The Zygon Who Fell to Earth)

The Eighth Doctor and Lucie later met him in Nadir Motorway Service Station in 2008 after he diverted them from their course to Blackpool. He was suffering from photomelanoma after being in Pat's form for over 20 years and knew that he was going to die. He sacrificed his life so that he could save Lucie's life. (AUDIO: Death in Blackpool)