In version 104e, the poster is not of a dead flower, but a poster of two monsters one pink, the other blue, that look like their fighting. The poster is still on the wall when both characters are asleep. ETA: If you chainsaw the poster a hole will appear in it that will transport Urotsuki to a small black room inside the wall with flashing floor lights. There is a small pyramid to the right that cannot be reached. The purple "cat" that's with the long black haired girl actually looks like a Clifairy. Since this game used to have Pokemon references, we could say it's a Clifairy, especially since the drawing is so similar.