It took me some time, but for the confused, here you go. This is episode 16.5 from the second season, a backstory episode that delves into the relationship between of Kuroko and Aomine, how they were and how they became. Aside from the drama and setup, it feels like a chill and very cute episode, showing the OG Generation of Miracles team, I believe, it's even the first time Akashi is shown to be active in a game. They all look very young and middle-school-esque for the first time, something that really bugged me whenever they would show a related backstory on the parent show.