If you let me dream a little, would ask that the confession was as follows:
Keiko, Ran and Mrs. Komatsu are taken together a tea and initiate a conversation:
Mrs Komatsu: Girls, what kind of relationship do you have?
Then Ran answered the question with an innocent little accident while quietly taking his tea.
Ran: We are girlfriends
Keiko and her mother spit drink surprise while still Ran quietly taking his tea as if nothing had happened. Then Keiko responds angrily:
Keiko: RAN !!!
And Ran finally realizing his accident responds with a wide face of shame:
Ran: AH !!!
(Small fanfic created based on the end of chapter 6 Prism, xd)