At the first moment after the breaking of glass, Leto slid quickly to stand behind Oswin, his movements blurred and unearthly. His Bene Gesserit training had not been forgotten. Still, he didn't leave. Instead, he scanned the inside of the shop, and found no one inside. It was a relief to know that no one had been hurt.
No one...
The sound coming from Oswin made him rethink that assessment.
"Oswin," he said gently, "I'm sorry to have... "
He was indeed very sorry. He knew he'd hurt her, somehow. He didn't understand exactly how, but he recognized it.