Monsterpedia

The Monsterpedia, sometimes referred as the Monster Encyclopedia, is an encyclopedia of monster database.

The Monsterpedia consists of 5 different tabs:

Info
On the Info page there is information as well as a background story of the monster. 

Data
On the Data page the Monsterpedia tells the level of the monster as well as the HP (on Normal difficulty, Hard and Hell give the monster more HP).

Below that it show how many times Luka has been defeated by the monster. This is in both story and recall mode.

Finally it also displays the monster's techniques. Techniques are grayedout until Luka "discovers" them, as in receiving the attack successfully. Techniques can be clicked on to learn how many times the monster has used it against Luka as well as how many times the attack made him come. Note that few monster techniques can only be discovered in certain situations and sometimes on Hard difficulty. 

Pose
The Pose page display's the monster's various poses, including facial, body, and bukkake. 

CG
CG, also known as Computer Graphics, shows rape images performed by the monster. Like monster techniques, CGs can only be seen if the rape was successfully performed. 

Recall
On the Recall page, players have the option to re-fight the monster or review the rape scene.

Monsters can be re-fought on Normal or Hard Mode, as well as choose to try and fight the monster on "Hell" difficulty, which is needed for an Achievement "Won a Fight on HELL Mode". However, Hell-mode monsters are extremely difficult and are almost unbeatable. Re-fights can also be performed to try to discover all of the monster's techniques and rape scenes.

If there are more then one rape scene the page will list them as "Rape Scene 1", "Rape Scene 2", etc. Each one those rape scenes have to be individually unlocked by certain conditions, often receiving a certain type of attack. Otherwise this option is grayed out. 