Hard Butter (하드버터) – 안아줘 (feat. Ginger)
Track 02 from Single "Now is the time"
Release Date: 2018.12.21
Hard Butter (하드버터) – Color (feat. Yezzin)
Track 01 from Single "Now is the time"
Release Date: 2018.12.21
Hard Butter (하드버터) – No Filter (feat. 한수연)
Track 01 from Single "No Filter"
Release Date: 2019.04.25