A fourth drama CD, titled Sono Christmas Candle no Akari ga Yureru Toki... (そのクリスマスキャンドルの灯が揺れる時…), was released with the special edition of Volume 6.5 on July 22, 2014. The fourth drama CD contains a character song by Yukino Yukinoshita and Yui Yuigahama (Saori Hayami and Nao Tōyama), titled "Kimi to Merry Christmas" (君とMerry Christmas).
A transcribed (written) version is included as a bonus chapter in Volume 6.5 (July 2014).
It provides details about what happens after the joint Christmas event with Kaihin Sougou. It is a large portion of Hachiman's Christmas break.