Aries waited, tilting his head slightly to the side to listen to his brother's footsteps until he wasn't able to make them out anymore. It looked like, for now, he was safe.
Which meant it was time to get rid of the evidence. Once Scorpius had somewhat forgotten about it, Aries assumed he could always go get the book from where he dumped it later. Unless it was found.
Just so long as it wasn't found in his room, he didn't care.
Crossing back to his bed, Aries leaned across it to tug the book free from where he'd jammed it earlier. He tucked it under his shirt, fully aware that it was probably an iffy hiding place at best before he headed out of the room and made straight for the staircase downstairs.
He was walking quietly enough... he just had to hope that he didn't run into anyone along the way.