Novel info
Anti-NTR Man: Tomboy Sister Bully

Yuuto Sakurai, the ANTI-NTR MAN, has been transmigrated into the body of a pathetic, background character who’s supposed to be the main protagonist in an NTR story. He’s excited—his mission is clear: baseball the NTR antagonist’s ass.
But this time, his opponent is craftier than expected; maybe requiring more than just the usual brute force...