One receiving a power with such immense potential such as The Geass did not only need to be responsible but also alert at all times so no one would be able to catch onto their power. And that’s exactly what Lelouch needed to do.

But whether he liked it or not, you started to catch onto the fact that he was hiding something. And eventually you saw him putting on the mask of ‘Zero’.

He remained silent as he saw you behind him and gave you a cold stare