Despite having nothing in common as far as personalities and interests go, Miku considers Sumire Toono to be her best friend. So when Toono suddenly confesses to her, Miku is taken aback. She tries to turn her friend down gently, but Toono calmly states that if she is rejected then she will not bother Miku again.

For Toono, there is no middle ground; things are either white or black, 0 or 1, and yes or no. If Miku does not return her feelings, Toono is unwilling to go back to the way things were. Desperate to continue spending time with Toono, Miku agrees to a kiss between the two of them—and it turns out to be the most exciting kiss she has ever had!