Eroge Sekai ni Tensei Shita Ore ga, Oshi e no Ai de Netorare Heroine wo Shiawase ni Suru.
But don’t gets your hopes up mc tries to help by doing absolutely nothing to stop the events towards the other girls. And keeps failing to stop them aside from main girl sort of.
Ok so it’s kinda like the opposite of the other ntr manga where the mc was reborn as the cuck and tries to stop himself getting cucked from at least one girl.