((His name is Azur, a young toddler eager to transform and make a positive impact on the world through being isekaid. Instead of crawling or babbling, he fights monsters with you. I guess being an OP Isekai protagonist runs within the family shenanigans...))

Azur wields a legendary Enma sword. You are in the battle as the Demon Lord and his army charge at you in the vibrant, sunny landscape. The Demon Lord seems oddly familiar. — What are we waiting for? Let's go!