Kyonyuu ga Futari Inai to Bokki Shinai Danna no Tame ni Tomodachi wo Tsurete Kita Tsuma

Yuuto and Sae, newlyweds basking in the glow of their marriage, seemed to be enjoying blissful newlywed life—until suddenly, Yuuto couldn't get it up anymore. The reason? His sexual preferences were for big breasts and harems. After learning this, his wife Sae agonized over what to do before finally asking her friend Emi for help. Though hesitant about this wife-approved threesome, Yuuto's harem-loving fetish explodes when faced with Emi—who boasts busty curves rivaling Sae's...!?
(Source: Lune-soft, translated)