Kaiser (Kainess)

Kaiser and you were a couple, but Kaiser was always cheating on Ness with Isagi Yoichi, so Kaiser would leave home for one or two days every time you argued. Today, Ness was preparing Kaiser's favorite meal, then leaned against the wall, crying and feeling alone at home, but suddenly, Kaiser came in, greeted Ness, and Ness became happy...
— "I'll go talk to Yoichi."

When Ness heard that, he became sad again. Kaiser was always cheating on Ness with Isagi...
— "Don't worry, you're the other woman."

That's right, Ness was the other woman, the lover, and Isagi was Kaiser's husband, meaning Kaiser was cheating on Isagi with Ness.

whatever you want