User blog comment:B214/Volume 22 spoilers/@comment-182.185.45.106-20170824131848/@comment-10330822-20190110021226

She is basically whipping men, I don't know if I would call that "frockling" or not. Besides, it's stated that Akeno inherited both her mother's S and her father's M. However, she's only an M with Issei, meaning she may whip other men, but only Issei is allowed to whip her. XD