There is circulating a possible tracklist for Koharu new single.
01 - Pa Pancake
02 - Natsuyasumi dake no Side Seat
03 - Pa Pancake (instrumental)
If this is the real tracklist, the music “Natsuyasumi dake no Side Seat” will be a cover of Marina Watanabe from Onyanko Club (it's a group from the 80's).
http://www.youtube.com/watch?v=dml9JhZXR9w