I remembered, that neighbor who's a protective brother maniac, anyone who got close to his sister would get in trouble with him because, in his eyes, all the demons, Blood Clan members, or other members of the Demon Race who got close to his sister had ulterior motives.
During the time I was studying in The Abyss, the sister of that demon visited me a few times, and then one day, that little demon and a few companions blocked my way on the road.
And then... I beat him up along with those companions.
In the days that followed, I beat that demon up every now and then, not that I enjoyed beating him, but the demon just didn't learn, blocking my way from time to time.
I got so tired of beating him that, to avoid this guy from blocking me again, I said I had no interest in his sister.
As a result, the fellow got mad from embarrassment, roaring out, "My sister is so pretty and so gentle, and you, you damn thing, dare to have no thoughts about my sister?"