The masses of Japanese text make this one VERY difficult although not entirely unplayable.
The gameplay is in the form of an adventure game commonly termed as a dating or romance simulator. You play a girl trying to decide which boy to date out of three possible suitors.
The movements and decisions are made through loads of icons within a menu and the immense depth of the realism and user interaction of the game means that without a knowledge of the Japanese text you will be well a truly stuck.
It may be possible to get a limited distance into the game by simply muddling through but you won't get as much fun as you would if you could read it.