College sophomore Makoto is full of anxieties about love. One night in the park,when he's practicing professing his love to an imaginary beau,a stranger called Shiro overhears him. Those words "I love you" intrigue Shiro so much,he takes up residence in Makoto's apartment! A demon that lives off words,Shiro grows bigger from eating pleasant words,and loses strength when he hears sad words. Shiro teaches Makoto everything about filling the void in his body and soul. Before he knows it,Makoto's first love has begun...!!