Sapphire
- Digital2,000 JPY
| 1 | Upheaval Feat.Rose |
| 2 | Until You Rise Again Feat.Kevin |
| 3 | Edelweiss Feat.Rose |
| 4 | Walk Feat.夏色花梨 |
| 5 | Calender Feat.夏色花梨 |
| 6 | Eight years Feat.Kevin |
| 7 | Confort Feat.夏色花梨 |
| 8 | warm bed Feat.Rose |
| 9 | Undead Feat.Kevin |
| 10 | アオイトリ Feat.GUMI |
| 11 | Until I Disappear Feat.GUMI Kevin |
| 12 | Recollection Feat.Kevin |
| 13 | Winter Fall Feat.GUMI |
| 14 | For The End Feat.Rose |
| 15 | Don't Look Back Feat.夏色花梨 |
| 16 | nobleness Feat.MAI |
| 17 | Lullaby Feat.夏色花梨 |
| 18 | Breathing Feat.Rose |
| 19 | Ametrine feat.夏色花梨 |
| 20 | Foot Point Feat.夏色花梨 |
| 21 | Won't stop diarrhea (しろ・こなー＆HK PROJECT) |
ヘヴィでエモーショナルな楽曲を展開するHK PROJECTのアルバム