Why the hell are there so many 10 star reviews. This is honestly the first time I've given a 1 star review and I know that due to the way to the score is calculated the 1 stars have less effect...
I don't see the problem here, it's just a oneshot of a highschool girl purifying ghosts with holy water. then her brother finds out her secret as a purifier and is implied he starts helping her later.