An scan from the upcoming issue of Weekly Shounen Jump
magazine will announce that Kuroko no Basket 2nd Season
's sixth Blu-ray/DVD volume will include an unaired special. The sixth volume will be released on June 22, 2014.
The scan shows that the special will be episode "41.5" and will cover how Kuroko
first met each other.
Source: Scan via ANN
Kuroko no Basket: Mou Ikkai Yarimasen ka