Soaping Up My Stepmom In The Shower

I was caught off guard when I found my Step-Mom in the bathroom, taking a shower. I was even more surprised when she requested my assistance. She justified it by saying she wasn't my biological Step-Mom, which made it acceptable in her eyes.
It felt strange to me, especially when she invited me to lather up her buttocks. While I always knew she had quirky tendencies, I never imagined she'd express a desire for physical intimacy. Despite feeling uncertain, I couldn't resist her undeniable attractiveness.
I eagerly seized the opportunity to engage in sexual activity with her, promptly taking her from behind in the shower and climaxing onto her visage.