OK Music has an interview  (Japanese only) up with Kiiyan and e-zuka regarding the new single. They talk about their influences for the songs, and hopes for their 10th year.

Particularly amusing was the interviewer telling Kiiyan that female fans seem rather taken with his sweet, high tone on 「追憶の輪郭」. Kiiyan responded that the song was something of a personal challenge, to stretch his range.

The interviewer also said that they felt 「wish」was a love song from Granrodeo to their fans.