I'm always amazed at how these "otome games" always blame the victim.
Basically, the ML has a fiance. He cheats on her in all aspects except the physcal one, or he even kiss the "heroine".
When the "villaines" complains about the infidelity she is called on her jealousy and meanness. Then, that criticism is used as justification to the affair, purposefully ignoring that the jealousy was a consequence of the infidelity and no the other way around.