yeahhh i dont like this MC, he kinda has an inferiority complex (he remember what his sister told him differently, keeps thinking about how her childhood friend is a true noble), he cares for her childhood friend but he it seems he sees her more like a battery than a girlfriend (even if they are not together yet).
Besides that Olivia seems less trustworthy with every new chapter, granting 3 super powerful skills that easily is already sketchy, but the fact that he needs to indulge himself in lust, gluttony and greed to regain LP and she keeps trying to lead him astray, welp seems pretty possible that all the LP he spends goes to her so it makes sense.