[He just continues to smile at that. How hypocritical, to try to frame self-interest as moral superiority (which is to say "YEAH RIGHT you ~meant what you said~"). See, this is why Sebastian finds morals kind of silly if one isn't prepared to stick to them 100%, no matter the situation.]
Then it is quite fortunate for you that your values were not compromised by your loyalties at the time. [Because surely "you have no right to touch other people's memories" applies to Porthos, too? And if the situation called for it, he would have disregarded that for the sake of his important people? "You'd do anything for them", after all.]