Green’s Dictionary of Slang

(US) weak, effeminate.

1902		O. Wister Virginian 110: ‘Riding and shooting and kissing the kids,’ sneered Trampas. ‘That’s a heap too pussy-kitten for me.’.
1929		S. Ornitz Haunch Paunch and Jowl 26: Whence will the real attack come to capture this little square which we have denied to them for their baseball and ‘pussy-cat’ games?