PuriPuri Chi-chan!!

An underground-dweller named Chi-chan wanted to come to the human world in search for sweets. After he finished his objective and he wanted to come back to his home, he would be stuck on the hole where he came from. He would then be saved by a girl named Yuka Saeki, who dug the hole where Chi-chan was stuck back there, and would then took care of Chi-chan in her home.