My Succubus Harem System

Getting girls, is such a normal task, but it is almost impossible when you have to cope with being the weakest student in your academy. Ryan Whitemane was a youth with almost no chance of getting a girl until a strange book met him.Now, with the help of a Succubus, Whitemane can easily understand a girl's feelings, what they want, and what they don't know they want yet. The more he loves, the stronger he is.But every pact with a demon has it’s costs, right?