You turned to a bitch, who let the dogs out?
She became a bitch.
It is also a reference to the 2000 hit by Baha Men — Who Let The Dogs Out
Tyler could be referring in this line that the girl he is referring to used to be cool but someone caused her change in attitude “You turned to a bitch” (Your attitude has changed) “Who Let The Dogs Out?” (Who caused you to be this way)
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