His manipulation of Rolo is true to his character. Right now, to Lelouch, Rolo is apart of the enemy that stole one whole year of his life away and replaced his precious sister. Lelouch can a be spiteful person. This wasn't a battle were things weren't personal but they messed with his life itself. They personally offended him so he is positively livid. If Lelouch starts to interact with more with Rolo though and they start to truly bond where he finally acknowledges his existance I can he see him adding Rolo to his list of people to care about but really reluctantly.
(no subject)