I feel so bad for the younger girl, even though did the do with the wife. Its shown that she's accidentally drawn to these people and have always ended up doing the do with married women. She actively has methods to avoid these women but still got stuck being attracted to the wife.
Younger girl? Oh? You caught my attention there.
Y'see, all this time, I was of the impression that Akari was the older one.
We can only guess, of course, as, even though we know Ayano is 35, we are never told Akari's exact age. But my guess was that they were very close in age, with Akari being slightly older.
My reasons? Well, mostly little details, like in chapter 2, page 13 - Akari: "I thought I'd found some sweet, innocent girl and seduced her." So Akari seemingly thought Ayano was the naive younger one in the couple?
In point of fact, she does act most of the time like she's way more experienced, and talks like she has a long history of broken romances behind her.
What makes you think Akari is younger? The difference in jobs?