@Nivek I forget which chapter, but the flashback was shown in full and, unless I'm remembering incorrectly, he fell for Maou-chan at first sight and became OP because he overheard that she likes strong guys; or something to that effect.
@Vincentius, @Nivek Chapter 3
He fell in love with her at first sight and walked out in front of her to proclaim it. She, of course, was always super weak to such talk and her minion(s) 'removed him' from her presence. He vowed to become someone strong enough to stand by her side.
@Vasqueztion Yep; it was bugging me that I couldn't remember, so I started re-reading it from the beginning and just finished that chapter. It was actually kinda funny how his personality somehow managed to completely change while remaining the same.
Is the yuusha just a ONE protagonist at this point?
Also big boobs, traps, lolis and now furries? The creator's just into everything but the kichen sink huh.