The Promised Rosary may be to your liking, there are other games where you dress up as a nun, Melty's Quest, Master of the Harem Guild has a priestess girl, Evenicle has an entire quest based on relationships with girls from the church. These are off the top of my head.
If you want the pure behaviour and the clothes then I don't really know much but most games with customization have at least one 'sacred clothing' so maybe you are into that.