Usagi Drop OP Single – Sweet Drops By sm2345 | August 17, 2011 - 4:32 PM |August 17, 2011 Usagi Drop The OP single of Usagi Drop has been released in Japan. Title is Sweet Drops and it’s performed by Puffy AmiYumi. Official lyrics will be updated on episode 07. You can visit Shinnoden or the mirror DDL to download the song. Alternatively, if you are supportive of them, you can purchase their single via Amazon. Bookmark the permalink.