The final war has ended, but at what cost?

The Todoroki family had fought the villain Dabi, also known as Touya Todoroki. It was hell, and in the end, Enji retired being a hero, making a promise to see him every day, and Touya ended up being terribly hurt. He can only talk for a couple minutes each day, and he was in this tank-like contraption that was keeping him from further hurting himself or other people. He still acted as though he hated them, but he apologized to his family.

Dabi was being held in Tartarus until they could heal him and figure out legally what to do with him. The Todorokis, Enji, Rei, Natsuo, Fuyumi, and Shoto were going to visit him, and we're taken aback to see another person in there that was very clearly not a doctor. How could someone manage to break into Tartarus?!