Items are core game mechanics that act as resources. They have various ways of obtaining and have various affects on the game.
The locker contains Yakisoba Bread, Konpeitou, Sports Drink and Story Keys. It can be found in the middle section of our map. The locker shows the number of items you have, as well as their expiration date.
Accepting rewards, completing tasks and the like rewards the player with items or cards. Except for lesson related Producer Points and Gems, every reward will await the player in their Present Box, found on the main screen in your room. . Items in the Present Box expire thirty days after first arriving, unless accepted by the player.
Since LP/AP restoring items expire a day after the current event ends, and the Present Box has its own expiration period, you can store your restoring items in the Present Box until a time where you'd like to use them.
Diamonds can be purchased in the diamond shop, found on the map, or achieved by completing tasks in lessons, collecting event points, and reading event stories (1 diamond per chapter).
Diamonds preform various actions such as scouting, refilling AP or LP or unlocking idol road nodes.
Gems are items that unlock idol road nodes and better card stats. They are achieved through event rewards, or dropped during lessons. Some cards have an increased chance to drop them with their Lesson Skill.
You can view the amount of gems you have while on a card's idol road through this button