So far this is average at best, definitely doesn't deserve the 8+ rating it currently has. While it presents a rather new kind of skillset for a MC, he has the massive flaw of being absolutely unaware of the goddamn world in itself, clearly the girl wasn't just a random girl, she lives in a castle, with fully geared guards, and then you're invited to a throne room, the sword for show that it's behind the man sitting in said throne isn't just any sword, even more if it's ugly as fuck. Plus the fact that he's oblivious of his own power, I can understand some self underestimation, but being almost a retard is seriously annoying, like, dude, you are able to hit a thousand things in one fucking slash, then you are told the monster you just beat would be a challenge for a whole party of S rank adventurers, seriously? You, the man that wants to be the best adventurer in the world has such a peanut sized brain that isn't capable of comprehending and making the power comparison with what you were just told? Man, come on... Also, less relevant, but if you're going to reject a reward, do so and stay true to what you said, don't play hard to get, she told you she'll stand and cry, then let her stay there and cry all she wants, you don't care about the reward, why would you care about that?