Here is the full list of all 9 White Wings ホワイトウィングス achievements.
「Happiness like Fine Sand」
「Happiness like Fine Sand」Hidden route
「Free Flying Wings」
「Flowers that Won't Bloom」
Second customs clearance
Fukihara Reika's favorability＞Miyazawa Moe's favorablility
「Fine Snow, A Memory That Can't be Returned to」
Fukihara Reika's favorability＜Miyazawa Moe's favorablility
Start the game for the first time