Puni Puni☆Handmaid

When three magical jewels mysterious fall from the sky, Earth is suddenly thrust into inter-dimensional affairs of the gravest importance, for these stones possess the power to transform anything they come in contact into humanoid creatures with sentience and superhuman powers. Thus begins an unforgettable adventure for a seemingly ordinary student, when three normal pets he has befriended, become beautiful women who seek to win his favor and heart. Where did these stones originate? Who seeks to claim them? Why? The answers will forever change this young man’s life, and those closest to him.

[From an old review by Nargrakhan]