The Social Life of Animals

 My cat and I play trust games.
 She wants nothing better than to bite my hand.
 She purrs when I permit her to put my hand in her mouth.
 She is merely gentle with her teeth.
 She wants me brave giving my face to her paws,
 gentle with her claws. 
 I am gentle reaching for her head
 to scratch behind her ears.
 We are mammals.