Book 2 : spinnoff to 'Takaga Koidaro'. Story of second pairing Sawaragi x Shuuya.
Book 1 : main story pairing Nagai x Honda
Book 2 : spinoff to Close The Last Door. Second story pairing Shouichi x Shunji as main story
Book 3 : chapter 4.5
A spinoff of Book 1 & 2
Book 1 : chapter 2_My Family is Interesting ; pairing Naito x Madoka 'En-chan'
Book 2 : chapter 8 & 8.5
Spinoff to (Book 1 chapter 2) pairing Kouta x Kusumegi
Book 1 : pairing Honda x Megumi
Book 2 : pairing Yukiya x Taiki
Spinnoff to Bittersweet Cafe. Prequel story when Megumi just a baby. Yukiya was in high school and meet Taiki as classmate.
Book 3 : pairing Shou x Kunie
Spinoff to Love or Pride. Sequel story after all the characters become adult. Shou is in dilemma. His faithfull to serve Taiki as a young master and future leader of the group, but his heart always belongs to Kunie_ Taiki's cousin and also rival to be next leader.
Book 1 : (multiple stories)
Chapter 5 : pairing Aizawa x Tsuji
Aiso Tsukashi