My stepfather's wife

It's been a while since I lived with my photographer's father-in-law, but her innocent wife, Yuna, couldn't forgive her for her stepfather's sexual harassment. One afternoon, Yuna, who had a lot of free time after finishing housework, was frustrated with her bland husband Seiichi, and ends up masturbating. Taking advantage of the fact that no one is watching, he exposes his lewd behavior, but by chance his stepfather comes home, he is filmed the whole story. When Yuna learns this, she instantly imagines what will happen next, and is terrified...