When Tyrion is lucid enough to face company, he finds that his father has taken over the role of the Hand of the King. He asks Tyrion instead to become the Coin Master, as Petyr Baelish (who held that role) is being sent to try and woo Catelyn's sister Lysa into marriage. Tyrion knows this role has been passed to him because of the extreme debt the crown is in: Twyin is setting him up to fail.
Sansa thinks she is to leave for Highgarden, and is to be married to Willas within a couple of days, but when Cersei gifts her a new gown she eventually realises it comes with a price. She is to be taken to marry Tyrion immediately. Horrified, Sansa realises too late the worth of her potential as a Stark just moments before her marriage.
The Unsullied are made eunuchs at a young age so that they will stay true to their masters, and not be tempted by women. They are given puppies to look after and kill after one year. The final part of their cruel training involves them killing a slave baby in front of its mother (and paying the owner for the loss of revenue). Any trainee who fails any one of the horrific tasks set for them cannot make it into the ranks.