That makes sense.

I'm working of a fic now, and was kinda conflicted about who's side A, and C would be on, but eventually I decided fuck it! TEAM DIO FOREVER!

I do Like Ros, even though she's weirdly out of nowhere, and just there to die apparently.
I'm thinking maybe she's the fraternal twin of Lucciola, who Lucciola never knew about(though Cicada did) because Delphine is a bitch like that. And maybe she was considered part of Aspis, but was more unfortunate plaything of Delphine which would explain a lot of her personality, and is something Delphine would totally do.