Kana-chan from Kanamemo. Her voice is high pitched o.o LOL I could've 게시됨 quite a lot of characters but Kana-chan needs 사랑 too x3
당신 might recognize this voice if 당신 listen closely... Another hint I kinda have to mention is she's the younger one with short, brown hair XD Now it's just plain obvious if you've seen the other show.