Walter had no means or warning to brace himself, dodge or try to catch whoever was falling on top of him. So he ended up crushed under Henry who was shrieking at him, completely leading Walter to believe he was being attacked by some large, falling Pokemon.

He scrambled to get out from under Henry, also shouting and holding Assumption tightly to his chest protectively. Upon seeing Henry he pulled himself to his feet, wrapping both arms around Assumption. "Henry?" Why was Henry falling on him?? He took a step back away from him. Not because of Henry...

Assumption was gripping tightly onto Walter's arms, eyes locked on Henry warily. His little body was trembling, no longer with happy energy. Walter swallowed. "I-I'm not-" He's not here for a fight, he's not here for Henry, he was going to meet Heather-