There are many incarnations of agyō and ungyō statues to be found around Ninna-ji. As I did not manage to get a shot of the other statue you’ll have to take my word on this, but the statue to the left is the closed mouth one of this pair inside of Kon-do. This statue is called Ryūtōki, the complementing statue is called Tentōki. In Kon-do they are both intended for use as candle stands though other versions carry lanterns rather than flat disks.
While you will not be allowed to take pictures, if you would like to see the inside of Kon-do one of the guaranteed ways to be able to see inside is to stay at the temple overnight. If you stay overnight at Ninna-ji you can attend morning prayers with the monks inside of Kon-do the next day. It is pretty impressive inside! I highly recommend taking a look if you have the chance!