I'm not a specialist but I'm pretty sure that yoga is of Hindu origin...
The physical Yoga that the west does is based on a type of Hindu yoga, but there are Buddhist and Jain yoga too. Did get a bit annoyed with saying that it was to Jesus though.
Keep in mind that the MC is not omniscient and by his own admission learned about yoga via watching videos of women doing it where he was more concerned with the women than the yoga. And iirc petal barely knows anything about it. So I think it's forgivable that they're not exactly well-versed on the philosophical origins of it.
I realize that this is completely off topic, but from personal experience I can confirm that it is fully possible to use Asian meditation techniques as a Christian. In fact, if you are a Christian but would (for whatever reason) like to delve into Asian mysticism, I strongly recommend to do so, rather than participate in the Asian ritual without understand it's implications.
IMHO the description on the OP makes the expected pace of the story pretty clear.
It's much more focussed.
I didn't care for Avalon, the game or the character, but I liked Petal quite a bit, so I would call them very different games.
Petal is the first of three VNs that complete a story arc. So effectively, this is the first of three chapters and as such is much more narrowly focused than Avalon. The writing is excellent and as the first third of the story it does an admiral job of setting the foundations, relationships, and by its end providing a pretty hot finale.
