@Mogima Wishes granted by a monkey's paw come with a terrible cost, so the joke is that readers/shippers wishing for more romance in the original series caused this cursed doujinshi to come into existence. I'm not sure if cromat was inspired by the original short horror story or one of the many adaptations in other media (including an appearance in the Bakemonogatari series).
I admittedly don't know much about Digimon, but if it's going to evolve into something, then off the top of my head it's either:
[ol]
[li]A large round yellow bird that likes to eat pasta, all sorts of Asian dumplings, and vegetable soup[/li]
[li]The full ayakashi form of Madara/"Nyanko-sensei" from Natsume Yuujinchou[/li]
[/ol]