There is an extra ghost available later in the game during Alyssa's final trip back to her house prior to the clock tower stage. Use Alyssa's sacred water bottle to unlock the seal on the room to the left of the door that had the boards nailed to it (Second Floor). Inside is the ghost of one of the mysterious Lodgers mentioned earlier in the game. This ghost is completely optional and as such, can be easily overlooked. The sentimental item for this ghost is also unique, and won't be found like other items. In fact, it's a normal item. Head all the way into the bathroom and use a Lavender Water on the Lodger Corpse as the sentimental item to help the ghost leave. *This information was supplied with help from the gracious members of the Clock Tower 3 discussion board*