"I'm less likely to forget where I put them, mostly." Skulduggery straightens his shirt out, then his jacket, and seemingly has the presence of mind to be ever so slightly embarrassed by the situation. Keyword: seemingly.

"I heard that if you got lucky, sometimes there'd be packages waiting for you at the sundries shop. Figured I'd stop by on the way and see if there was anything... well, lo and behold."

He taps the package that is pretty plainly clothes. He doesn't say that it's a special package from Friday, nor does he mean to imply that it could be nice clothes. But it sure seems like that's what he's doing!