Lilia is just an ordinary girl who works in a bakery. She spends every day happily with her childhood friend, Ronan. One day Lilia finds her body has shrunk. Moreover, she has grown cat ears and a tail?! She panics, jumps out through her room's window, and runs towards the town. And the first person she bumps into is the city guard, Ronan. 

One day you discover the other side of your partner you had never known. What is the truth beneath the masks? Each of them has secrets. The mask of "Big Sis" and "Luccretia Girl" she wears. The mask of "Lil Bro" and "City Guard" he wears.

Which one of them will be taken off first?