Space Slugs by Frances Pauli

When Xenobiologist, Dr. Murray, receives yet another phony wedding invitation from her galaxy hopping sister, she does what any good sibling would do. She drops her research and hops the first flight to some obscure planet at the edge of the civilized universe. But Zora’s weddings never manage to go off as planned, and before the cake is served, Murray finds herself imprisoned with the unapologetic bride. With the assistance of a mysterious android and the universe’s last living space slug, the two find themselves on the run in a stolen space ship with half the galaxy in hot pursuit. Thanks to Zora, it’s the least desirable half. Maybe Murray will get lucky, and the crash landing will kill her.