Responses
Maybe cause of regression? Since he is in a body of a child and you know from baby, to child, to teenager, and to adult, the body is not yet develop from the body of a child. And so maybe, the undeveloped body of the child, undeveloped brain, gives away his 30 years old morals... Just my thoughts for this... Or maybe he was a lolicon, or worse a pedophile in his last life

... This isekai really has a weird plot.. like. A 30 year old saying he can be in love with a child younger than 9. A 30 year old with naive and lofty view on life. Also his whole territory only has 1000 people. Like. That's a tiny village, not even a small town. If half of them are male. And half of that is of working age, and 30% of them are soldiers. Then their whole territory would only have around 75 soldiers. What in the world can you do with 75 soldiers?????
Even if half of the total male population are between 16-30, and all of them are soldiers for whatever reason, they would have max 250 soldiers. That's pitifully little.
Also, why would a territory with 50k people marry the favoured daughter to a tiny territory with 1k people??? The girl's ambition for a strong male household is also bloody misogynistic.
What.
Also, where's the mom??? She's ... just gone.