I married a goblin to rank up as an adventuer

Rusty Blade is your not so typical Low rank adventurer. He's one hundred and fifty years old and only rank D. Since adventures can only die in battle Rusty has lived long enough to see everyone he knew either die or rank up without him. He never gave up and one day it finally pays off when he meets a high level goblin in the forest. The goblin offers him a method to rank up that includes marrying the daughter of the goblin chief.

This is a short series that I'm writing while I work on other projects like "Demon Party". You can go ahead and judge this one by its cover. Thanks!