The moment that Ken heard Shinjiro come back, he immediately looked around the area before attempting to hide the cake on a giant lid. As quickly as he does so, he slowly turned around to see him approaching ever into the living room.

"H-Hi, Aragaki-san! When did you get home?"

He said with a nervous chuckle before his eyes looked at the nearby cake. Why no, he's not being obvious. What are you talking about?