Damien entered the castle without hiccups. Honestly speaking, all the credit belonged to this maid.
Although Damien had to time his entrance into the barrier to perfectly match the maid's movements when she brushed it, that wasn't actually a hard task for him.
To his eyes, the unhurried movements of a mortal could be watched by the microsecond. It was like he was watching the scene in super slow motion, so he didn't have a difficult time at all.
After he entered the barrier, he mimicked the technique Zara used to stay within his shadow. However, because he wasn't proficient, it wasn't nearly as smooth.
For one, he couldn't expand the shadow into a massive subspace as Zara could, so he was forced to squeeze into the already existing space within the shadow, causing it to move awkwardly.