Breed noun – A number of persons or things that are grouped together because they have something in common. Succession and breed are semantically related. In some cases you can use "Succession" instead a noun "Breed". Nearby Words: breeding, breeder
Basically, the Deepspawn are The Worm That Walks meets The Assimilator, so by introducing a larval colony to a rapid succession of mammalian and crustacean hosts; extracting them at the proper time, they can more or less "breed" them into weapons or siege-beasts.
Despite this, she publicly renounced her intent on marrying, since offspring will only breed violence due to inheritance and Succession Crisis (a big, big part of the story in fact) and thus will remain without spouse.