I'm a Minor Villain, But the Protagonist is Obsessed

When I came to, I had possessed the body of a small-fry villain in a fantasy novel my younger sibling had been reading. And not just any villain, but one who is killed after kidnapping the protagonist under his father's orders! The problem is, by the time I realized this, I had already kidnapped the protagonist. Furthermore, this situation had already repeated itself several times. ‘Possession and regression? Is this some kind of combo set?’ The goal is to survive. To do that, I must get on the good side of the protagonist I kidnapped! --- “I-I’m n-not scared! I l-l-like you, Big Brother!” “…Why on earth?” I could have just let it slide, but at this moment, I couldn't. What could ...