Reformation through Digestion
Originally the three were orphans until they were forced to take the mantle of priest by certain circumances. Leading on the run down building as best they could with the help of the nuns, somehow they managed to stay afloat through mysterious means. Nobles that cut funds had strangely disappeared the next day.
Now its an upcoming church with the head priests collecting girls by shrinking them! Attempting to 'reform' their crooked ways by correcting them and making them part of their holy church! Though when an individual protests too long they swallow and digest them beliving that in the next life they'll come back cleansed of their sins.
What sins have they commited you ask? Being too delicious for their own good, dressing in ways that catch the attention of the priest. Simply being in their way while being hungry is enough cause to cleanse them of their sins. At least according to Raziel that is.
In reality they're just like any other church providing help towards others by their own definition of what they deem is best for the individuals. If there's a single common trait found amongst them all it seems belly rubs is often something they enjoy.