(sorry beforehand if this is not the best forum)
How would I go about writing a fictional book about Catholic mer-people? Hypothetically speaking, whether in fiction or through some weird scientific development, if a Christian sect of mer-people (that is, real human beings who live exclusively under the sea for biological reasons) were to exist, how would their baptisms take place? Would pouring water over the initiate’s head be easier or harder? What about other sacraments?
Of course, it must be asked if the idea of a Catholic mermaid is the same as a square circle. As an alternative to contesting my above question, can anyone prove that this concept is impossible, even for fiction?