At little, Fukuta was bullied for being chubby but at his side was always his beloved Aoi-nii. Now Fukuta doesn't remember the face nor the name of his beloved oni-chan but dreams about him, who was once at his side, while waking up with tears in his eyes...

3 short side story extras following along and after Sayonara Alpha's main story.

Toujou Aki lives with his younger step-brother, Saku, who is a university student. Instead of going home to sleep though, Saku will stay out with as many women as possible, to the point of being a man-whore. Aki, on the other hand, harbors a deep hatred for women – enough to make him nauseous being around them. Aki's one secret is that he would do anything for his brother. No matter what it is. However, everything can change in an instant during the silence of three minutes.

People fear lawyer Yuuya due to his strict nature, but his kouhai during his university time, Kanade – currently a NEET – is attached to him. Yuuya initially hated Kanade's unexpected character, but his puppy-like behaviour slowly crept into Yuuya's heart for the first time. However, there's a feeling that Yuuya wants to keep hidden from him…

A high school boy who's always considered himself to be an Alpha finds out that he's in fact an Omega. And his destined partner is a kid?