I suppose one would like all the girls to be flexible, but I like the detail that some aren't. After all if they were all flexible, none of them would be special in that respect. Bianca, Heather, Sarah and Mel being less flexible may not be complimentary to them, but it is a detail about them and I always appreciate new details. They are girls who do yoga but aren't as passionate about it as others.
But what do you think about the rest of the girls? Which of them are more flexible? I wouldn't expect it of Josy and Maya, but Sage might be. Zoey has athletic hobbies, but that doesn't automatically make her flexible. Quinn and Riona don't strike me as the kind of girls who exercise regularly, but they might do it for sex. Lily most definitely is very flexible. It should be safe to assume that flexible is in the job description for all the Pink Rose girls. Nora's exercises were more strength based so she might not actually be that flexible, but it wouldn't be surprising if she did those exercises too. Jade has found the time to train so Cathy should have too, but this might be something different about the two. Can't really guess about other girls.