Hm.. this game is like a tribute to recent game created by chinese dev that has been onhold or might be abandoned because their region's strict law (the one with Cthulhu and same graphic as this one)
Oh right, for those who struggle the storeroom worm thing, pick the penny on the art room and buy a weird thing on vending machine to pass...
Go to the library on the 3rd floor while still wearing the normal school uniform. Nothing to see really, she just talks about books and then finds a diary page.
Worst thing is if you wanna see scene you need to skip through the bs 1000 times then lose and to advance again go through the "cutscene" raping x button. There should be some skip this is terrible.
if you're talking about the one in the bottom left, you need to get the unlabeled key next to the gate and head to the 3rd floor. There should be a locked classroom at the right end of the 3rd floor, and inside there should be a shadow thingy near the lectern. It has three rape attacks that it cycles through, you need to refresh the room after escaping one attack.