Legendary Youngest Son of the Marquis House

Synopsis:

Jack Valantier passed away after exacting vengeance on the Thulcaan Empire. However, just when he thinks everything is over, he is transported back to when he was 14 years old! Everything is as he remembered, from his naughty and wicked family to his faithful servant and caring sister. However, Jack has decades of experience from his previous life to his advantage this time around! He is prepared to punish them severely, and those who have wronged him will bear heavy costs. He is immune this time around.