I'm not a big fan of prologue stories because you always know how it ends roughly. I rather like the idea of a second independent goblin, with new women of their own. The contents of corrupting, addicting cum and breeding are already important contents.
I already have a rough idea (I like that with the orcs a lot):
A goblin was able to flee from a group of orcs who wanted to keep him as a slave / life ration. The orcs have moved upstream. He was able to escape (by jumping into the river and holding onto a large piece of driftwood). This did not go unnoticed and the hurricane leader sends 2 young orc women to recapture him. With the words: This is your probation to grow up, if you fail you don't have to come back. He can catch you by a trick (can be a pit where he takes the ladder away or a cave where he can block the entrance). And then he starts to feed the women ..... So he has his first brood mares. You move on to a village where almost all the men were drafted and died in the war (there are only old women and children in the village). The village is threatened by a danger that normally only battle-hardened men take care of. They are so desperate that they even ask the goblin for help (he solves the task with his first 2 playmates). So he can steal the trust of the village and start corrupting .........
(P.s .: my english is not the best and i google used for the translation
)