Lorelai Benson is an atheist who practices daily meditation. She wasn't raised in youth group, she didn't go to Catholic school, she was homeschooled by two very progressive parents (dad is fully human, mom is part-mer), and she passed her various college placement exams. She was thankfully raised in non-fundie circles. She's never really gone to church. There's really no reason why she needs to be in habit. But she toured a convent once when she was trying to find new direction in her life after she had an accident during a surfing competition. It wasn't for her, but hey, at least they gave her a free habit. Why not use it?

Ever since getting in touch with her merfolk roots, Lorelai has had the same Halloween costume idea every year: the Mermaid of Zennor (or, as her Cajun accent renders it, "the Mawmaid of Zennaw"). She's created even more mythology than the people of Zennor, Cornwall came up with, like how Saint Senara herself had the most beautiful feet that were as effective as a siren's song, just with a 100% less fatality rate. She's even come up with the accoutrements, including getting a toe ring with a cross on it (because nuns are known for their bling). And since she's also into Sue Monk Kidd novels, Lorelai's found herself attracted to Kidd's second-banana novel, That Time I Fell in Love with a Monk aka The Mermaid Chair. If it has mermaids in the title, she's for it.

This takes place about a year after Lorelai gets the memo that her "Bee Chawmuh" just isn't in love with her at all. She's recovered. She moved on. She found herself a new partner, the second Bee Charmer...

(checks notes)

a changeling who feels way more comfortable being a fox than a human, often attributing said disconnect down as related to the relative mundanity of humanity.

Yup, Marian/Cordy is back - in speech bubble and fox form (albeit clothed because i'm not good with naked bodies) - and she's been lured in by Lorelai's powerful siren "song" (more like her warbling off-key to "Let it Go"), only to be hooked in even harder by those fleshy fishy feet, fresh from their part of the habit. Lorelai refers to Marian/Cordy is "Cordy" - it's good practice, plus what is Cordy but the less anxiety-ridden version of Marian? Also, whatever form Marian/Cordy inhabits at that moment is usually a good sign of figuring out which alter is in control.

Lorelai Benson belongs to me.
Marian/Cordy belongs to  nothere
The Mermaid of Zennor belongs to Senara d'Zennor Enterprises, Inc., a division of the Betterman Tourism Bureau, a division of the Betterman School for Children Who Can't Read Good and Want to Learn How to Do Other Stuff Too.