The Taste of Lingering Affection is Strawberry Milk

My sentiments exactly. I think she displays some tsundere behavior at first, but she's so adorable all throughout the story that you hardly even notice it. I would be a bit concerned about her clumsiness though if they married and had children... Wouldn't want her to trip and fall with the baby, you know?

Twin tails turning into twin buns in the bath is a nice touch.

In the author's defense, it would have been weirder for Kiyori to keep the ribbons on while bathing, and that scene acts as the perfect conclusion for this story in the event that the author doesn't continue it; it allows us, the readers, to presume a happy ending on the part of the young couple, after all.