What is the meaning of かい and き in Google's Summer Solstice Doodle?


I was wondering what the meaning of かい and き is for the Google Summer Solstice
Doodle pictured here: ![enter image description
here](https://i.stack.imgur.com/a7lfM.png)

I'm guessing it has some relation to summer, but what?




Unfortunately, it is unlikely that these Japanese letters have anything to do
with summer.

These are mascots of [Kaikai Kiki Co.,
Ltd.](http://english.kaikaikiki.co.jp/whatskaikaikiki/), a company run by
[Takashi Murakami](http://en.wikipedia.org/wiki/Takashi_Murakami), the artist
who painted this Google Doodle. Also note that the same mascots appear in the
[Winter Solstice Doodle](http://www.google.co.za/webhp?hl=en), too.




Unfortunately, it is unlikely that these Japanese letters have anything to do
with summer.

These are mascots of [Kaikai Kiki Co.,
Ltd.](http://english.kaikaikiki.co.jp/whatskaikaikiki/), a company run by
[Takashi Murakami](http://en.wikipedia.org/wiki/Takashi_Murakami), the artist
who painted this Google Doodle. Also note that the same mascots appear in the
[Winter Solstice Doodle](http://www.google.co.za/webhp?hl=en), too.

