When the Coach added all that extra lotion for her "lower stretches" I just knew this would literally slide into some ANAL play. You know, to loosen those tense GLUTES... But nope, nothing; what a missed opportunity! Maybe next time! Otherwise this artist is routinely knocking it out of the park and I look forward to more sequels!!!
Like the chorus of the song from the 1970's says so well (figuratively, rather than literally): "Another One Bites the Dust."
EDIT: I say "Another One" because I have a feeling Sakurai-chan is neither the first female student, nor the last to be subjected to Coach-san's *koff-koff* "special massage technique".