The phrase "titular hero" refers to the main character or protagonist of a story or piece of literature, who is also the title character or has the story named after them. Full definition
from Cathy Come Home, Loach tackles the impacts of austerity and mealy - mouthed bureaucracy on families and communities once again, this time with a rousing central performance from comedian Dave Johns as titular hero who won't take it no more. (hellisforhyphenates.com)
You take control of titular hero Rayman as you travel through various worlds trying to save the Teensies from evil wizards. (switchplayer.net)
Back in October, we learned Robert Downey Jr. was in final talks to join Chris Evans «titular hero in Captain America 3, which was later revealed to be Captain America: Civil War. (filmcutting.com)