Here is a short clip of Erika chan cracking walnuts in an interview. I cut out most of the talking, it is Japanese language and I don't want to make subtitles (too lazy ).
In the beginning she is interviewed before making a femdom AV, she is dressed as a nurse. The guy asked her what she wants to do with male testicles. She make her fingers like a scissors and say like "cut!" She want to ******** a man!
In the second part she in sitting in a chair holding a pair of walnuts. The walnuts represent a pair of testicles. She feels and massages them, and then... "CRACK!" I like the end, see the smashed walnuts/testicles at her feet. She has a winning smile and is satisfied.