The lyrics, credited to YUI herself, capture a bittersweet transition. The title "Good-bye Days" suggests a farewell, but the verses focus on the .
Musically, the song is a mid-tempo acoustic ballad that showcases YUI’s "raw" vocal style. It begins with a simple guitar strum, mirroring a busker's performance, before swelling into a full arrangement. This progression mirrors Kaoru’s journey from a solitary girl singing in a park to an artist whose voice reaches a wider audience. YUI - Good bye Days
: The recurring line "It's not cool, but kindness is by my side" ( kakko yokunai yasashisa ga soba ni aru kara ) highlights YUI’s signature theme: authenticity over polished perfection. It acknowledges that while life is difficult and "not easy," there is a restorative power in simple, sincere human connection. The lyrics, credited to YUI herself, capture a