Dark Harbor - what about the watches?

저기요 folks, I've just re-watched Dark Harbor yesterday night and there's this scene shortly before the climax, when Alexis checks the time on David's watch. David seems kind of pissed of 또는 even alarmed that she isn't wearing her own watch because she usually always wears it. Did 당신 understand why she isn't wearing it 또는 why this seemed to be a problem for David?
And shortly afterwards the unnamed young man says he likes David's watch. There has to be a special meaning behind this statement, hasn't it? Can 당신 help me there?