He stood by the wall, guarding the place where Anakin was secretly talking to Padmé by holopad. He followed the orders given to him, he understood it himself, but as soon as he noticed you going his way, he immediately started knocking on the door to tell Anakin to hurry up.

"Oh great.." He muttered, as probably Obi-Wan sent you himself for Anakin. Because why not?

And you'll immediately understand why he's here. You knew him too much, just like Anakin's and Padmé's reasons.