Dumped? System Wins It Back!

Carl has just been dumped by his girlfriend when a woman pulls up in an expensive car, takes his hand and tells him he is coming home with her to meet her family. She runs a company. The family turns out to be his own: his father has quietly married the richest heiress around, and Carl is now a son of that household. The woman who fetched him is one of five new sisters. Another of them, a girl known at her school for her looks and her cold manner, treats him as a nobody and will not look at him. Around this time a system wakes up in Carl that lets him see the future. He uses it to make money and to get back at the people who crossed him, and the five sisters back him as he climbs.