Mount Revenge ~ Hametsu Suru Made Miteite Ageru, Sareduma no Fukushuu

Nagiko Asakura, a former model now working at an apparel company, lives with her husband Ryosuke, who works in the same company’s sales department. Though busy as a dual-income couple, she believed they were living an ordinary but happy married life. But that illusion shatters when she discovers that Ryosuke is having an affair with his coworker, Erina Shiozaki. Worse still, Erina has no intention of hiding it. She constantly provokes Nagiko and tries to one-up her at every opportunity. Faced with humiliation and betrayal, Nagiko finally decides to fight back—and begins her revenge. (Art Lapsa)

https://www.cmoa.jp/title/351002/