Anyone can request image and manga uploads using the Upload Request form https://dynasty-scans.com/requests And yeah, this image was one that was requested be uploaded.
That's one hell of an age gap... granted any character x Cagliostro is an age gap, the only one that'd be different would be Lucio and that's just an age gap in the other direction...
Hurray for age gaps!
Edit: So I was looking around to try and find Danua's age again because I though she was really young but she's apparently like 17 so that knocks away most of my point from before.