Since Nino didn’t comply with Miku’s request. Maybe Miku will now ask Fuutarou herself for what he wants for a present, as oppose to asking others to find out for her. I hope with this way, she will face him properly and not weave around with deception like all the other times.
And it looks like Fuutarou is doing his own little investigation into who kiss him. As we see Fuutarou in page 10, seem to be examining Yotsuba’s eyes. And from the last three chapter, he was looking at the lips of Ichika and Nino.
When Yotsuba bring up Miku as his potential interest, Fuutarou is surprise and question why she brings up Miku, possibly wanting to know her reasoning but Yotsuba didn’t really give him a proper answer for his inquiry.
Now, it’s theory time, hopefully it’ll be less bias toward Miku than my first theory on who's Rena.
[Who is the Kyoto girl?]
In this period, everyone is very similar to one another, so it’s hard to pin down who’s who. But what period was this from? Was it before or after their mother’s death, or before she was hospitalised? I say that Fuutarou meeting Kyoto girl, is prior before her mother death as the picture we see in Ch.14, show that all the quint was smiling. Whether it was before or after their mother being hospitalize, I do not know.
Then we get into why she is alone by herself. Originally, I thought it was because she was lost herself, but after thinking about it. I believe that she chose him to follow him. When Fuutarou first met her, she rescue him from the police by said that saw everything, but what if she really DID mean that she saw EVERYTHING. From Fuutarou lagging behind the group, to his departure and eventual sulking at the base of the steps. What if she chose to follow him because of how similar her circumstance are to him?
Keep in mind that we do not know the entire event. We all know what kind of impact Kyoto girl had on him but what about her? What kind of impact does Fuutarou has on Kyoto girl? Given how Fuutarou is at this age, I can’t really come up with any suitable answer except, he is there with her.
Which leads me to question, does Kyoto girl even remember or know that the boy she met five years ago is Fuutarou at the start of the series? It’s possible that with their mother’s death, plus a five-year gap may have overshadow and fuzzy the memories of Kyoto and it was not until much later that Kyoto girl realize who Fuutarou really is.
People have speculated as to the identity of the unknown childhood boy from ch.68 as Fuutarou itself, but I personally will have to disagree with that. One, I don't think that trip last more than one day, given how light those kids were carrying and I did not once see any adult supervision for Fuutarou’s group if this was going to be a more than one day trip for “elementary school kids”. Two, there doesn't seem to have any indication from Fuutarou himself that he ever meets Kyoto girl again for a second time in the past. And three, where will they find each other again after that day? From what I know they didn't exchange any contact number or address. Four, if they met each other again why didn’t Fuutarou ask for her name. Five, that silhouette does not match how Fuutarou looks like five years ago.
Also, it seems that teenage Rena and Kyoto girl are one and the same. So, if you want to know my thought and reasons as to who I think teenage Rena is you can search for my name in the comment forum of Ch.68, but short answer is that I think the likely candidate is Miku, followed by Ichika and then Itsuki.
While I don’t know how to prove that Miku is Kyoto girl other than through teenage Rena, but author and artist alike tend to like their weird symbolism and foreshadowing. So, forgive me if this theory sounds a bit too outlandish and far-fechting but, looking at the card Fuutarou had on hand when he played with his friends, we could maybe use them as representatives for the quint.
From
(K/H, K/S, 6/S, A/C, A/H)
To
(K/H, K/S, A/C, A/H, A/S)
Now I don’t play cards, but I do know a bit about pattern. From the first hand, the odd one out is obviously the 6 of Spades, with the other card Ace of Clubs being a very minor difference. Fuutarou then discards the middle card and we resulted with our second hand.
The odd one out is still the middle card but the one that he draws by discarding 6 of Spades is the Ace of Spades. So, by that logic the candidate for Kyoto girl is either the Ace of Clubs or Ace of Spades. If we go by the order in which they were born then Miku or Itsuki are the likely candidate, if we go by the order of the picture shown in ch.14 then Itsuki and Ichika are the candidate.
I had read a comment from the anime discussion of episode 3 at Reddit, that elaborate the meaning of each of the quint's name. What caught my attention was Miku’s name, the second half of her name mean “Beautiful Black Jewel”. Both middle cards and the new card are black, furthermore the new card could be viewed like a black jewel, so there’s that.
But regardless of whether people argue if Kyoto girl is either Ichika, Miku, Yotsuba, or Itsuki. We eventually need to address the comment that Nino made when she saw the photo. I have three ideas on how and why Nino could vaguely recognise young Fuutarou. One, is right at end where Kyoto girl leave with her father, the rest of the quint were nearby, and they saw him. Two, while Kyoto girl is with Fuutarou, her family went looking for her when they notice she was not around and after awhile Nino caught glimpse of her sister with a blonde boy but wasn’t able to reach them, so she informed their father about it. Three, Kyoto girl drew a picture of him at home and show it to Nino and presumably the others too.