>>45648144It's a ship but you can see either boob cracks or butt cracks.
There are two boob cracks visible now. That means this ship is cracked.
I mean either dictionary definition works.
adjective: cracked
1.
damaged and showing lines on the surface from having split without coming apart.
"the old pipes were cracked and leaking"
2.
informal
crazy; insane.
"you must think my family is cracked"
Both work in this context to explain a crack ship, however if an actual vessel has a crack in it, it may not be seaworthy. However where the dictionary fails me there is a slight (1%) chance that ship is actually slang for relationship, which my nerdy ass will never have.
In that context this may mean it's a relationship that would fall apart almost instantly, a suggestion usually made in jest to arouse a response of humor.
I hope I helped friend. Stay safe. The internet is a scary place sometimes!