These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
YMMV: Kin-iro Mosaic
Big Lipped Alligator Moment: This is a light-hearted comedy series, so it's not like anything is meant to be taken too seriously... but the musical number Shino narrates from the middle of episode 12 onward pretty much comes out of left field. How does one go from talking about chuunibyou to the Little Mermaid anyway?
It probably doesn't help that she suggested Alice give her a lock of her hair as a birthday present. Or how her friends think Isami doesn't let Shinobu use the computer in case she finds (and eventually starts collecting) pictures of blonde girls (accompanied by some very excited breathing by Shinobu in the Imagine Spot).
Alice's Friendly Rivalry with Karasuma and/or Karen over Shinobu is definitely this.
Aya is guilty of this as well. Episode 4 really takes the cake, where she practically obsesses over what's written in the letter, and by the end, is visibly relieved knowing it wasn't what she thought at all. Also some of her Tsundere antics are directed towards Youko.
Even Youko is suspicious, saying that she "likes looking at the curves of a woman's body". Not to mention her saying that she couldn't like anyone more than she likes Aya.
Episode 11. Alice explains that in England, Christmas is a holiday spent with families, not lovers. She later says "A Japanese Christmas is a day to spend with Shino!", which is practically a confession.
Later she confess in a more explicit way, but in English, to her saying "I like you", even Youko remarks it.