Rei has a crush on Sekiya, who's always kind to girls, to the point that she's hesitant Sekiya will be always by her side...
Includes 4 other oneshots:
空色NO.青 (Sora Iro NO. Aoi)
ゴキゲンだぜ! (Gokigen da ze!)
空に咲く花 (Sora ni Saku Hana)
愛の▼愛のしるし(Ai no Ai no Shirushi)