Duck's manga / #magic(3)

MC is a poison user, which is an infamous user type. He wants to heal people after an incident that almost killed his sister

A broke engeineet student dies and reincarnates as a lousy son who leads his family to their downfall. He wants to change that future, or at least prevent his own death, by gaining as much money as possible. He isnt the MC of the story, but he will work them to the bone for his goals.