Tyrion

In his cell which only has three walls and a side that opens up to a 600 foot drop that has a slight downward slope towards the cliff, tyrion is continuously torments by Mord. Tyrion keeps thinking about how he wished he didn't have such a loud mouth. Tyrion then thinks that since his loud mouth got him in the dungeon that surly it could also get him out. Tyrion then bribes Mord by telling him that he will share some gold with him, to go to Lysa and tell her that Tyrion would like to confes for his crimes which is exactly what Lysa wanted. Lysa is then pissed because Tyrion is confessing to little things such as whoring and then demands for a trial. Lysa then asks if tyrion has someone who will step up in his behalf. Bronn then comes forwards and says that he will stand infront of tyrion. This chapter brings numerous questions to the surface. Why did Lysa claim that tyrion was HER  prisoner and that he will not be harmed? Also I wondered about the importance of the Blue Sky, I think the writing was about the cliff and the blue sky you would be falling through but why did the author emphasize the BLUE? Also why did Bronn stand for Tyrion?