That Child is the Strongest

I have a younger sister with a big age gap between us. You could say she's in what's commonly called the "terrible twos" phase. Year after year, she's become more and more selfish. Since our parents are busy, I'm the one who has to look after her, and I've been doing so, but I'm still only in first year of junior high. I'm Shigeyo Saruwatari, the older brother who gets pushed around by his younger sister. With instincts sharper than anyone else's, she's my younger sister, Riyo Saruwatari. Hibiki Otone is her childhood friend and a small knight who's sworn to her future. I just went to pick her up from kindergarten and then—a transfer to another world!? Stop it!! Look carefully!! That's a bird of prey! You idiot! It's not a dog! It's not a lizard! It's a dragon!! Am I going to be pushed around by my sister in this other world too!? When I finally got this chance at another world!!