I'm a little confused. Did that particular ghost have any specific relation to the bracelet or the granny? I know his aura was strong so being near him caused it to explode. But did he follow her just because of the friend or because of the granny/where they were going? And why did the friends bracelet only blow up at the end when granny whipped out her super bracelet? And did he go back after the bracelets were gone or just eventually he wandered off?
@TheStuffedUnicorn he has no connections to either. The ghost was just so malevolent that the holy beads that she bought and what the granny gace her were practically useless.
The normal holy beads only made it itchy but the one that the granny gave her made it irritated, thus snapping and breaking the beads
@TheStuffedUnicorn What LayZzz said, notice every time he blows a bracelet up he says it itches, and when Hana comes closer he also starts reacting intensely, leading up to the end with the super bracelet affecting him the most blowing Hana's up as well.
As for why he followed them, they probably caught his attention too much.