The two had secretly harbored feelings beyond friendship, but they had been living separate lives. Upon reuniting after a long time, 'Haruka' saw that 'Seika' was more beautiful and refined than ever before, making 'Seika's' desires uncontrollable, ultimately leading her to make advances on 'Haruka'. Initially confused, 'Haruka' found that 'Seika' had awakened the carnal desires she had long suppressed... thus, the two became entangled in forbidden lesbian lust.
