Welsh gods, while their distinctive pantheon with their own distinctive mythology, are considered part of overarching Celtic mythos. Rhiannon, in specific, is connected to the Celtic horse goddess Epona.
I don't think it's anything crazy about gods or whatever with Lou, though. This is simply a case of "This is exotic in a European manner, and I can't butcher the pronunciation because Stevie Nix pronounced it for me."
One of his friends asked him about that name on Tell a couple weeks ago, and he gave one of his typical, no-comment answers. The horse goddess thing might make sense, given that he's a crotch-boob brony, but
Lou himself doesn't seem to know or care why he picked that name, so you're probably right; it's no more complicated than "eh, whatever, exotic name, good enough".
Gotta say........I lolled hard when I saw the Buffalo shooter is a furry and possibly a brony.
Lou's been remarkably quiet about the Buffalo shooter. I would have thought he'd be all over it, but aside from the requisite "I know this happened" tweets, he's mostly dropped it. It's dying like the Slava Ukraini Saga, and if Lou found out the shooter is a brony fur, that might account for it.
Lou failed as a man, failed as a writer, even failed as a porn hoarder.
The fact that Lou considers "my porn drive got reformatted" to be an ordeal on par with not having a place to live is both incredibly funny, and utterly tiresome. It's probably also why he's been depressed lately:

He's not been doing much; retweets are mostly about gunz, BLM, and men asking for money to pretend to be women. Jordan Peterson made a spicy tweet about fat people, so of course Lou is joining the fatty crusade:



There's a lot of jokes to be made here, but I'm not really sure why Lou is knocking JBP for eating meat; cats are obligate carnivores. Have I missed something? Has Lou decided to go vegan and swear off tacos and chicken wings?
Lou continues to take pride in his white ancestry:

Soon, Brothers. Soon.
Other stuff; Lou attacks a woman for making a point about medical ethics (
@Aunt Carol , any insight?), wishing for more wishes, Ichigo looking to start shit, and gay Gargoyles with Werechicken:




BONUS: Lou reveals his vote!
