Lady Shay was pissed that her slave did things without consulting her. Most of the time he ended up messing and she did not like that. She felt that he had to learn his lesson and that is why she opted to crush and humiliate him so that he would know he needed to run things by her before doing them as it was her house and she was his boss. So she used her smelly socks to crush him.
Lady Shay likes to show losers what she is capable of before she punished them. She sent a warning to this loser by crushing a giant doll and turning it into a tiny one. She destroyed it and she almost buried it into the ground as she crushed it. She warned him that he would suffer the same fate if he did not stop bothering and pissing her off all the time.
Lady Shay has a very good memory. And most of it comes in handy in remembering those who have pissed her off. She likes to revenge and punish them. She does it twice as bad as they did to her. She used her giantess powers to turn this guy into a doll. She then crushed him and she tortured him with her giantess ass. He never messed with her again.