The Day I Became a Butterfly is a volume which contains six chapters, each a different story:
1) <amlink subject="10655">The Day I Become a Butterfly</amlink>
2) <amlink subject="10655">You at the end (Hate ni Aru Kimi)</amlink>
3) <amlink subject="10655">The Lonely War</amlink>
4) <amlink subject="10655">Blue Cat Tunnel</amlink>
5) <amlink subject="10655">Tokyo Alien Ulala</amlink>
6) <amlink subject="10655">Planet Yours</amlink>
(Source: ActiveAnime)