This was good simple one shot manga. My guess is that Kyoto animations is going do what the stretch manga did. They are going to go as close to gayness as possible without crossing the boundaries of actual confirmation with words that reina and kumiko have feelings for each other.
At the end both reina and kumiko will never confess to each other and instead kumiko will go with shuuichi. Thus there will be suggestive gay scene between reina and kumiko that don't go gay all the way. I hope that kyoani does go fully gay but that is only wishful thinking on my part.