Father of Eren and foster father of Mikasa. He is a renowned doctor who was well respected in the District of Shiganshina after he saved the village from a mysterious viral epidemic by developing vaccines.[ch. 3] He also provides a medical house call service to the people of Shiganshina and to various towns in addition to having a network of contacts within the Corps of the Shiganshina district. Thought to have gone into hiding after the fall of Wall Maria, Grisha became an Original Titan during the chaos and used his state of being to devour Freida Reiss to take the Coordinate from the Reiss Family as he wiped most of them out. Grisha later turns Eren into an Original Titan so he can have son eat him and become a Titan Shifter.[ch. 62] Before his death, Grisha tells Eren that he hid a secret which he refers to as the "truth" in the basement of their family home.[ch. 3] His memories of the event having been fuzzy at the time, Eren eventually learns the truth of his father's final actions and feels betrayed while realizing that the "truth" is connected to the Coordinate power.[ch. 63] While heading to the Orvud District of Wall Rose, Historia comes up with her own conclusion that Grisha had a more logical reason for killing her sister and giving Eren the Coordinate powers, upon realizing what Rod had in mind.[ch. 67]