This mostly deals with the two siblings detailed in the synopsis. The stories are all connected (aside from the one-shots).

Story, 5: The two one-shots are extremely short, and while they offer mildly interesting premises, they simply didn't have enough time to develop into anything beyond average. The "Dissolving" series was interesting, but I didn't really like any of the chapters until "Interview with the Devil", where everything from the previous chapters comes together (which actually gave a satisfying conclusion).

Art, 7: There are some cool pieces here, namely for fans of biological horror (mostly to do with dissolving). It's solid otherwise as well.

Characters, 5: I thought the idea of a constantly apologetic character (Yuuma) was intriguing, but his character didn't extend much beyond that, nor did his sister's personality. All of the side characters were fairly flat as well.

Enjoyment, 5: It was a quick read, but it didn't thrill me until the final chapter.

Overall, 5: Fans of Ito's other works that contain longer plotlines ("Gyo", "Uzumaki") may find this more appealing than the various volumes that collect his one-shots (as this volume offers a multi-chapter story), but I don't think it's really on par with those works, in terms of storytelling or characters. The final chapter in this volume almost makes it worth the read, but I wouldn't recommend this particular story, other than to superfans of Ito Junji.