1
Forbidden Bonds
Hakuro and Mioto share a secret, intimate relationship despite being half-siblings, while Hikaru and Akimi harbor similar forbidden feelings for their own siblings. Through a calculated conspiracy orchestrated by Akimi and Hikaru, the four are brought together to confront their hidden desires. Ultimately, they accept their unconventional bonds and decide to embrace their love for one another in a shared, secret arrangement.
2
The Third Sister's Awakening
While Ayu and Izuru indulge in their usual intimate routines, they draw the attention of Kokone, who is struggling to study for an English test. After teasing her for her curiosity, Ayu and Izuru decide to initiate Kokone into their secret activities. Though initially reluctant, Kokone soon succumbs to the pleasure, resulting in a heated three-way encounter that ends abruptly when she remembers her academic responsibilities.