No one from the Templar Temple realized that the prisoner on the lowest floor had been released while under Mayonaka Yoru's protection. But having regained his freedom, Luciel Dawn did not leave straight away. After all, there are too many opponents outside for him and Mayonaka Yoru to effectively escape with only the two of them. So they decided to wait till the Dawn Family arrived to pick him up.
The former Cardinal decided to remain in the Dungeon in order to reclaim all of the dungeon's energy and elemental abilities. Given enough time, this extracted power would return to his body, restoring him to his former peak of strength while repairing his ailments. Mayonaka Yoru offered to be his bodyguard. Of course, Luciel Dawn ensures that whatever spells or parasites were implanted in the young man's body are removed, and while he hasn't accepted this punk as his prospective son-in-law since he hasn't inquired his son about their relationship, they are still friends despite that.