What does Wemmick have a unique ability to do?

Wemmick has the unique ability to lead two separate lives. When he leaves work, it no longer exists. When he leaves his home, he's all business.

When I go into the office, I leave the castle behind me, and when I come into the castle, I leave the office behind me. If it's not in any way disagreeable to you, you'll oblige me by doing the same. I don't wish it prefessionally spoken about.