After the opening movie has finished playing, the title screen will be displayed.

If this is your first time playing, please choose [NEW GAME].
To load your saved data, choose [CONTINUE].
To play a specific chapter, choose [CHAPTER].
After clearing the prologue, four different stories will become available.

Touch with 1 finger: Next, choose
Touch with 2 fingers: Open menu
Touch with 3 fingers: Skip all
Flick up：History
Flick left：Hide text
Touch and hold for 1 second: Auto

At the beginning of the game, each possible selection of a romantic interest has its own distinct world. Because of this, you can enjoy separate routes immediately from the start.
In addition, within each route, each character's background will vary somewhat.
e.g.: In his route, Shin is your childhood friend, but in Ikki's route, he is a co-worker at your part-time job, etc.

However, your target character's personality and characteristics will remain unchanged.
(Only your relationship to him and the surrounding environment will change; his character will not.) You can enjoy a different relationship with the characters in each world as you explore the story.

Before losing her memories, what kind of life did the heroine lead, and with which character...?
Can she trust the people who appear before her...? Your progression through the mysteries of each story is completely different for each route.

Because of her memory loss, the heroine has no memories of he who is her boyfriend.
As the story progresses, you will come to know more about his personality and your surrounding relationships, and develop a new romance.

The amnesiac heroine will have about a month, starting from the 1st of August, to regain her memories. She will investigate her past and her surrounding relationships, as well as attempt to interact with the man who is supposedly her boyfriend.

Orion will act as reliable support, sometimes lending advice, sometimes chiming in with witty commentary. He may be trapped within the heroine's mind, but he possesses some convenient spirit traits, such as the ability to freely cut off his feeling of sensation, or being able to hear her thoughts.

In this situation, where you don't remember your relationships, your cell phone is an important source of information. There will be times when you will need to decide what course of action you will take in response to contents of a text from your boyfriend.

Until she regains her memories, the heroine's choices will become her main way of asserting herself.
Try to choose the best option by predicting the person's response and your relationship up to this point.

There exist three types of parameters in-game.
They will increase or decrease depending on the heroine's choices.

The basic content are as follows:
＜Affection＞
The amount of affection the heroine has for the current target.
It could also be considered the heroine's strength of love.
The higher this number is, the better the possibility of reaching a Good Ending.
＜Trust＞
When the heroine's relationship with her target gets better, this parameter goes up. When it gets worse, it goes down. This number represents how favorable the relationship is in areas separate from romance.
＜Suspicion＞
This amount rises every time the target suspects the heroine has lost her memory.
The higher this parameter is, the more possible it is that you will achieve a Bad Ending.

If you fulfill certain requirements, a rose icon will be displayed on the upper-right side of picture thumbnails within the Gallery. If you touch pictures that have a rose icon, depending on the touched area, voice clips will play that give the effect of having physical contact. Feelings that previously couldn't be shared will be expressed, bringing the two of you closer together.

Explore mini-games where you can use touch controls to play against each character. If you win against three out of the five characters, a special still image will be unlocked.