My Beautiful Girlfriend Cheated on Me, so I found Comfort in Having a Relationship with Her Little Sister

In the dramatic web novel 'My Beautiful Girlfriend Cheated on Me, so I found Comfort in Having a Relationship with Her Little Sister,' readers are drawn into the complex relationships of Koichi, Mana, and Yume. Koichi discovers Mana's betrayal, leading to a surprising twist as Yume, Mana's younger sister, reveals her hidden affections for Koichi. As Yume sets her sights on winning Koichi's heart and disrupting her sister's relationship, themes of love, jealousy, and betrayal unfold in this captivating tale of adult drama and romance set in a school life background.