Not usually into the cuckquean thing but I dig it. I was expecting more of a stinger, though, like she was on birth control or something. It seems like wifey would have gotten more used to it after 9+ months if she's coming over every night. Maybe some pages with them talking about it, Minori ashamed to admit it turns her on, or some panels where she's not just standing there listening, she's masturbating. And especially since the artist isn't great at conveying complex emotions through facial expressions, it might have been good to have Mamoru outright saying he liked it, or wanted Tanaka's body or loved breeding her. Something to show that Tanaka wasn't the only one into it.