The two previosuly sang the theme song “Staccato Days” for the TV anime first season in 2013, the second OP song “Mainichi Koharu Biyori” for the second season in 2014, and the theme song “Omoide Creators” for the OVA Omoide Present in 2017.
18 days prior to its TV premiere in Japan, the official website for the TV anime adaptation of Siro’s mountaineering-themed manga Yama no Susume/Encouragement of Climb has started streaming a three-minute sound-only preview for “Irochigai no Tsubasa” (The Wings in Different Colors), the ED theme song for its upcoming third season.
It is the fourth duet song by Yuka Iguchi (Aoi Yukimura) and Kana Asumi (Hinata Kuraue) for the anime series.