楽観的な処世術 https://twitter.com/Hoshina_drops 歌唱無し音源 https://drive.google.com/file/d/1SHb8nYQtInN7jYUpohHwGvn3KerM7nXh/view?usp=drivesdk
http://www.nicovideo.jp/watch/sm41952736
