" The first morning Simon had been at Amatis's house, a grinning lycanthrope had showed up on the doorstep with a live cat for him.
"Blood," he'd said, in a heavily accented voice. "For you. Fresh!"
Simon had thanked the werewolf, waited from him to leave, and let the cat go, his expression faintly green.
"We'll you're going to have to get your blood from somewhere," said Luke, looking amused.
"I have a pet cat," Simon replied. "There's no way. "

― Cassandra Clare , City of Glass (The Mortal Instruments, #3)