Yogyakarta was once a kingdom on its own (with a king (Sultan) and his own court). However, with Indonesia's independence, it agreed to become part of Indonesia as a province with "special" status. Til now, the people are known to still hold and practice the ancient Javanese mystical beliefs and traditions. According to these beliefs, mount Merapi plays a very important role to the extent that it has its own gatekeeper who leads a yearly ceremony called Labuhan. In this ceremony, the Sultan's personal belongings are offered to the mountain.
Regardless of this, Mount Merapi has been revered by many because of its beauty and the fertile soil surrounding it. Millions of photos have been taken of it and many people have climbed its slopes. But with the eruption, the grounds are now covered in ashes and rescue workers occupy the area to attend the evacuees. A big shout of respect to all.
Pic by ~sisasapigila on deviant art (http://sisapigila.deviantart.com/gallery/#/d2jb800)