Tensei Kizoku wa Taishi wo Idaku! ~Gekokujou Kizoku no Isekai Harem Senki~

Osamu Takahashi, who died in an accident, was reborn as Isaac, the second son of the Marquis Welrod family, in a different world of a romance game. However, he is bullied by his brother-in-law, and his first love already has a fiancée... Realizing that he is in a difficult environment even in another world, he makes a decision. "You're in a good position, give it to me!" This is a story of a harem war in a different world of a game, where a man walks the path of supremacy without reading the atmosphere and becomes the king――!!